6503 - Construction of Water & Sanitary Sewer Improvements Phase 2 For the Denton Energy Center, 3.Statement of Work/ Specifications (2)Geotechnical Engineering Report
DME ‐ Jim Christal
Substation and Transmission Towers
Denton, TX
October 17, 2016
D&S ENGINEERING LABS, LLC Jim Christal Substation and Transmission Towers
Denton, Texas (13-0278-19)
TABLE OF CONTENTS
1.0 PROJECT DESCRIPTION ...................................................................................... 1
2.0 PURPOSE AND SCOPE ......................................................................................... 1
3.0 FIELD AND LABORATORY INVESTIGATION ....................................................... 2
3.1 General ............................................................................................................. 2
3.2 Laboratory Testing ............................................................................................ 3
3.2.1 Unconfined Compression Tests ............................................................... 3
3.2.2 Unconsolidated-Undrained Compression ................................................ 4
3.2.3 Overburden Swell Tests ........................................................................... 4
4.0 SITE CONDITIONS ................................................................................................. 4
4.1 Stratigraphy ....................................................................................................... 4
4.2 Groundwater ..................................................................................................... 5
5.0 SOIL MOVEMENT ANALYSIS ................................................................................ 6
5.1 Estimated Potential Vertical Movement (PVM) ................................................. 6
6.0 FOUNDATION RECOMMENDATIONS .................................................................. 7
6.1 Shallow Foundations – Mats ............................................................................. 7
6.2 Drilled Shaft Foundations – Structures, Equipment and Transmission Towers 8
6.2.1 Lateral Load Parameters ......................................................................... 9
6.2.2 Drilled Shaft Construction Considerations ............................................. 10
7.0 EARTHWORK RECOMMENDATIONS ................................................................. 11
7.1 Subgrade Modifications .................................................................................. 11
7.2 Additional Considerations ............................................................................... 13
8.0 PAVEMENTS ........................................................................................................ 13
8.1 General ........................................................................................................... 13
8.2 Behavior Characteristics of Expansive Soils Beneath Pavement ................... 13
8.3 Subgrade Strength Characteristics ................................................................. 14
8.4 Flexible Pavement Design and Recommendations ........................................ 14
8.4.1 Full Depth HMAC ................................................................................... 14
8.4.2 Soil Preparation for Flexible Pavements – Lime Treatment ................... 14
8.4.3 Aggregate Base ..................................................................................... 16
8.5 All-weather Roads and Parking ...................................................................... 16
8.6 Non-Paved Areas ............................................................................................ 17
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9.0 SEISMIC CONSIDERATIONS .............................................................................. 17
10.0 LIMITATIONS ........................................................................................................ 18
APPENDIX A – BORING LOGS AND SUPPORTING DATA
APPENDIX B – GENERAL DESCRIPTION OF PROCEDURES
APPENDIX C – UNCONSOLIDATED-UNDRAINED TRIAXIAL COMPRESSION RESULTS
1
GEOTECHNICAL INVESTIGATION
DENTON MUNICIPAL ELECTRIC
JIM CHRISTAL SUBSTATION AND TRANSMISSION TOWERS
DENTON, TEXAS
PROJECT DESCRIPTION
This report presents the results of the geotechnical investigation for Denton Municipal
Electric’s new Jim Christal electrical substation and transmission towers to be constructed
immediately west of the new Denton Energy Center. The project site is located at 8201
Jim Christal Road, Denton, Texas. The proposed construction will include transformer
pads, switchgear and transmission control buildings, and transmission towers. No earth
retaining structures are currently planned.
The site is currently generally undeveloped, and is primarily utilized for agricultural
purposes. The site is covered with bare, plowed soils and occasional vegetation. Based
on visual observations, the site is generally flat. Photographs showing the condition of the
site during the field portion of this investigation are included below.
PURPOSE AND SCOPE
The purpose of this investigation was to:
Identify the subsurface stratigraphy and groundwater conditions present at the site.
Evaluate the physical and engineering properties of the subsurface conditions for
use in the geotechnical analyses.
Provide geotechnical recommendations for use in design of the proposed
structures, as well as recommendations for related site work.
The scope of this investigation consisted of:
Drilling and sampling twelve (12) borings to depths of about 30 to 40 feet below
existing grade and three (3) borings to a depth of about 10 feet.
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Laboratory testing of selected soil and bedrock samples obtained during the field
investigation.
Preparation of a Geotechnical Report that includes:
o Evaluation of Potential Vertical Movement (PVM).
o Recommendations for foundation design.
o Recommendations for earthwork.
FIELD AND LABORATORY INVESTIGATION
3.1 General
The borings were advanced using a truck-mounted drilling rig, that was equipped with
continuous solid flight and hollow-stem augers, and wet rotary coring equipment.
Undisturbed samples of cohesive soil and weathered bedrock strata were obtained
using 3-inch diameter tube samplers that were advanced into the soils in 1-foot
increments by the continuous thrust of a hydraulic ram located on the drilling
equipment. After sample extrusion, an estimate of the material stiffness of each
cohesive soil and weathered bedrock sample was obtained in the field using a hand
penetrometer.
The soils and bedrock materials were periodically tested in situ using Texas Cone
penetration tests in order to examine the resistance of the bedrock materials to
penetration. For this test, a 3-inch diameter steel cone is driven utilizing the energy
equivalent of a 170-pound hammer falling freely from a height of 24 inches and
striking an anvil located at the top of the drill string. Depending on the resistance of
the bedrock materials, either the number of blows of the hammer required to provide
12 inches of penetration is recorded (as two increments of 6 inches each), or the
inches of penetration of the cone resulting from 100 blows of the hammer are
recorded (as two increments of 50 blows each).
The bedrock strata present in Borings B7, B10 through B12 and B15 through B18
were drilled and sampled using a double-tube core barrel fitted with a tungsten-
carbide, saw-tooth bit. The length of core recovered (REC), expressed as a
percentage of the cored interval length, along with the Rock Quality Designation
(RQD), is tabulated at the appropriate depths on the Log of Boring illustrations. The
RQD is the sum of all core pieces longer than four inches divided by the total length
of the cored interval. Pieces shorter than four inches which were determined to be
broken by drilling or by handling were fitted together and considered as one piece.
All samples obtained were extruded in the field, placed in plastic bags to minimize
changes in the natural moisture condition, labeled as to appropriate boring number
and depth, and placed in protective cardboard boxes for transportation to the
laboratory. The samples were described and preserved in the field. The approximate
locations of the borings performed at the site are shown on the boring location map
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that is included in Appendix A. The specific depths, thicknesses and descriptions of
the strata encountered are presented on the individual Boring Log illustrations, which
are also included in Appendix A. Strata boundaries shown on the boring logs are
approximate.
3.2 Laboratory Testing
Laboratory tests were performed to classify the soil types. The samples recovered
during the field exploration were described by a geotechnical engineer in the
laboratory. These descriptions were later refined based on results of the laboratory
tests performed.
Samples were classified and described, in part, using ASTM and Unified Soil
Classification System (USCS) procedures. Bedrock strata were described using
standard geologic nomenclature.
In order to determine soil characteristics and to aid in classifying the soils,
classification testing was performed on selected samples as requested by the
geotechnical engineer. The tests were performed in general accordance with the
following test procedures. The classification tests are described in more detail in
Appendix B (General Description of Procedures).
Moisture Content ASTM D 2216
Atterberg Limits ASTM D 4318
Percent Passing No. 200 Sieve ASTM D 1140
Additional tests were performed to aid in evaluating soil strength, volume change, and
other physical properties, including:
Unconfined Compressive Strength of Soil Samples ASTM D 2166
Unconfined Compressive Strength of Rock Cores ASTM D 7012
Unconsolidated-Undrained Triaxial Compression ASTM D 7012
Overburden Swell Tests
The results of these tests are presented at the corresponding sample depths on the
appropriate Boring Log illustrations presented in Appendix A. The results of the
unconsolidated-undrained triaxial compression tests are presented in APPENDIX C.
3.2.1 Unconfined Compression Tests
Unconfined compression tests were performed on selected samples of the
cohesive soils rock cores. These tests were performed in general
accordance with ASTM D 2166 for soil and ASTM D7012 Method C for rock
core samples. For each unconfined compression test performed, a
cylindrical specimen was subjected to an axial load applied at a constant
rate of strain until failure or a large strain (i.e., greater than 15 percent)
occurred.
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3.2.2 Unconsolidated-Undrained Compression
Unconsolidated Undrained triaxial strength tests were performed on
selected samples of the unweathered shale bedrock in-tact rock cores.
These tests were performed in general accordance with ASTM D 7012,
Method A. During an Unconsolidated Undrained triaxial test, a cylindrical
specimen is first subjected to a confining pressure that is approximately
equal to the in-situ confining pressure of the material at the depth from
where the sample was obtained. The sample is then subjected to an axial
load that is applied at a constant rate of strain until either failure or a large
strain occurs (greater than 15 percent).
3.2.3 Overburden Swell Tests
Selected samples of the near-surface cohesive soils were subjected to
overburden swell tests. For this test, a sample is placed in a consolidometer
and is subjected to the estimated in-situ overburden pressure. The sample
is then inundated with water and allowed to swell. Moisture contents are
determined both before and after completion of the test. Test results are
recorded as the percent swell, with initial and final moisture content.
SITE CONDITIONS
4.1 Stratigraphy
Based upon a review of recovered samples and the Geologic Atlas of Texas,
Sherman Sheet, this site is determined to be located in an area underlain by soil and
bedrock strata associated with the undivided Pawpaw, Weno Limestone and Denton
Clay Formations, with Quaternary surficial alluvial deposits overlying the native
materials. While shown on the geologic map, Quaternary surficial deposits were not
observed within the near surface soil samples in the borings. The subsurface
materials are indicated to be lower Weno Limestone and upper Denton Clay strata.
The near surface soils consist of clays (CH and CL), which range from stiff to very
stiff in consistency, are dark shades of brown near the surface, becoming light brown
with depth. The native clay soils extend to the top of a weathered limestone layer at
depths of 1 to 10 feet below existing site grades.
The weathered limestone strata varied from 1.5 to 7 feet in thickness. The limestone
materials are very soft to moderately hard in rock hardness, highly fractured, and
contain Gryphaea (oyster) fossils. The weathered limestone strata extend to the top
of the weathered shale strata at depths of about 5 to 14.5 feet below the existing site
grades. The weathered limestone strata extends to the maximum depth of 10 feet
within Borings B19 through B21.
The upper portions of the shales present are differentially weathered, having been
leached by percolating waters. The zone of weathering extends to the top of the fresh
shale strata at depths ranging from about 15 to 21 feet. The weathered shale strata
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are very soft to soft in rock hardness, brown, gray and dark gray in color. Below the
zone of weathering fresh shale strata were encountered which are soft to medium
hard in rock hardness, dark gray in color and possess a fissile structure.
A Summary of the subsurface conditions encountered during our field investigation is
provided in the table below.
Table 1. Subsurface Stratigraphy
Boring
No.
Top of Weathered
Limestone (ft.)
Top of
Weathered
Shale (ft.)
Top of Fresh
Shale(ft.)
Total Depth
Drilled (ft.)
B7 7.5 14.5 21 35
B8 6 13 21 40
B9 10 12 22 40
B10 9 13.5 20 30
B11 8.5 10 20 30
B12 5 8 20 40
B13 5 8.5 15.5 30
B14 5 9 15.5 40
B15 3.5 5 15.5 35
B16 2 6.5 16 40
B17 1 5 15 35
B18 2 9.5 15.5 35
B19 5 NE NE 10
B20 4 NE NE 10
B21 4 NE NE 10
NE – not encountered
4.2 Groundwater
Groundwater seepage was generally not encountered during drilling and prior to the
introduction of water used for coring purposes. Groundwater seepage during drilling
was encountered in Borings B19 and B21 at depths of 9 and 7 feet respectively but
the borings were found to be dry at completion. Groundwater was not encountered in
Borings B13 and B20. The following day, groundwater was observed at depths of 4
to 20 feet below the existing ground surface. Groundwater levels may be anticipated
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to fluctuate with seasonal and annual variations in rainfall and also may also vary as
a result of development.
A Summary of the groundwater conditions encountered during our field investigation
is provided in the table below.
Table 2. Groundwater Conditions
Boring No. Seepage During
Drilling (ft.)
At Completion
(ft.)
After 24 Hours
(ft.)
B7 DRY* 25 7
B8 DRY NO 20
B9 DRY NO 7
B10 DRY* 20 20
B11 DRY* 20 20
B12 DRY* 20 20
B13 DRY NO DRY
B14 DRY NO 4
B15 DRY* 16 7
B16 DRY* 20 8
B17 DRY* 16 9.5
B18 DRY* 16 9.5
B19 9 DRY NM
B20 DRY DRY NM
B21 7 DRY NM
NM – not measured: NO – not observed
*Prior to introduction of drilling fluids for coring purposes
SOIL MOVEMENT ANALYSIS
5.1 Estimated Potential Vertical Movement (PVM)
Potential Vertical Movement (PVM) was evaluated utilizing a variety of different
methods for predicting movement and based on our experience and professional
opinion. Movements can be in the form of swell or shrinkage.
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At the time of our field investigation, the near-surface soils were generally found to be
in an average moisture condition. Based upon the results of our analysis and the soil
type, the PVM is estimated to be about 4 inches. Soil modification will be required to
reduce the PVM. Wet, average, dry are relative terms based on moisture content and
plasticity.
FOUNDATION RECOMMENDATIONS
The soils have the potential for significant post-construction vertical movement with
changes in soil moisture content. If potential post-construction movements can be
tolerated, a shallow (footing) foundation or mat foundation may be used to support the
various structural elements. If post-construction vertical movements on the order of those
described cannot be tolerated, consideration should be given to a drilled shaft foundation
system. Recommendations for subgrade preparation to reduce PVM are described in the
Earthwork Section of this report.
Please note that a soil-supported shallow foundation or floor system may experience some
vertical movement with changes in soil moisture content. Non-load bearing walls,
partitions, and other elements bearing on soil-supported elements will reflect these
movements should they occur. With appropriate design, adherence to good construction
practices, and appropriate post-construction maintenance, these potential movements
can be reduced.
6.1 Shallow Foundations – Mats
For large equipment pad shallow foundations, we recommend that structural loads be
supported on reinforced concrete, monolithic shallow mats founded in properly
prepared subgrade soils at a minimum depth of 36 inches below final exterior grades.
Mat foundations should be designed using a maximum allowable bearing pressure of
2,000 pounds per square foot when placed on prepared subgrade as described in the
Earthwork section of this report. This pressure may be increased to 4,000 psf if placed
on compacted aggregate base material that is at least 30 inches thick. We
recommend that mat foundations be a minimum of 16 inches thick.
Mat excavations should not be left open overnight. Concrete or engineered fill should
be placed the same day that footings are excavated. We recommend that a
representative of D&S observe all footing excavations prior to placing concrete to
verify the excavation depth, cleanliness, and integrity of the mat bearing surface. Any
mat excavations left open overnight should be observed by D&S prior to placing
concrete to evaluate the depth of additional excavation required. In the event that
reinforcement and concrete cannot be placed on the day final excavation grades are
achieved, the base of the excavation may be deepened slightly and covered by a thin
seal slab of lean concrete or flowable fill to protect the integrity of the foundation
bearing material.
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The bottom of all mat excavations should be free of any loose or soft material prior to
the placement of concrete. All equipment pads should be adequately reinforced to
minimize cracking as noted movements may occur in the foundation soils.
6.2 Drilled Shaft Foundations – Structures, Equipment and Transmission Towers
New building structures at the substation will likely consist of either conventional
ground-up construction, or of prefabricated metal buildings erected on pier-supported
steel frames suspended above the ground surface. For these structures, we
recommend a minimum clear space of 6 inches be provided between the bottoms of
grade beams or steel frames, and the final ground surface. Any appurtenances
connected to the buildings should be pier-supported and should also be isolated from
the ground surface by means of a void space.
Structural cardboard forms may be used to provide the required voids beneath the
grade beams or appurtenances for building structures. If carton forms are used, care
should be taken to assure that the void boxes are not allowed to become wet or
crushed prior to or during concrete placement and finishing operations. We
recommend that masonite (1/4” thick) or other protective material be placed on top of
the carton forms to reduce the risk of crushing the cardboard forms during concrete
placement and finishing operations. We recommend using side retainers to prevent
soil from infiltrating the void space, when forms are used to create the void.
We recommend that major structure loads, and other movement sensitive elements,
be supported on reinforced concrete, straight-shaft drilled piers bearing in dark gray
fresh shale encountered at depths of 15 to 21 feet below existing site grades. We
recommend those shafts penetrate a minimum of 2 feet into the fresh shale to utilize
the full amount of allowable end bearing. Drilled shafts may be designed to transfer
imposed loads into the bearing stratum using a combination of end-bearing and skin
friction.
We recommend the piers be a minimum of 18 inches in diameter. Larger diameters
may be required to accommodate anchor bolts, embed plates, or other geometric
considerations. We recommend using allowable bearing parameters as outlined in
Table 3 below. The allowable side frictions noted in Table 3 may be taken from the
top each stratum or from the bottom of any temporary casing used, whichever is
deeper, to resist both axial loading and uplift. As there is appreciable strain-
compatibility between the weathered and the fresh shales, the side friction for both
may be included in the shaft design for shafts extending into the fresh dark gray shale.
The allowable bearing values are summarized in Table 3 below.
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Table 3. Drilled Shaft Allowable Bearing
Material Depth Below Current
Grades (ft.)
Allowable Side
Friction (psf)
Allowable End
Bearing (psf)
Weathered Limestone
and Weathered Shale
B7-B12 10 to 22
B13-B18 10 to 16 1,200 N/A
Dark Gray Shale B7-B12 below 20 to 22
B13-B18 below 15 to 16 2,800 18,000
Drilled straight-sided shafts designed and constructed with these recommendations
could be subjected to total and differential settlements of small fractions of an inch.
The uplift tension forces caused by expansive near surface clays and other uplift
forces will be resisted by the structural load on the shaft plus the uplift side resistance
developed around that portion of the shaft below a depth of 10 feet below final exterior
grade. The uplift pressures due to expansive soils are approximated to be an
average of about 1,000 pounds per square foot of shaft area in contact with
overburden soils above a depth of 10 feet. The shafts should be provided with
sufficient steel reinforcement throughout their length to resist the uplift pressures that
will be exerted by the near surface soils.
Often, 1/2 of a percent of steel by cross-sectional area is sufficient for this purpose
(ACI 318). However, the final amount of reinforcement required should be determined
based on the information provided herein, and should be the greater of that
determination, or ACI 318.
There is no reduction in allowable capacities for shafts in proximity to each other.
However, for a two-shaft system, there is an 18 percent reduction in the available
perimeter area for side friction capacity for shafts in contact (tangent). The area
reduction can be extrapolated linearly to zero at one shaft diameter clear spacing.
Please contact this office if other close proximity geometries need to be considered.
We anticipate that a straight-side drilled pier foundation system designed and
constructed in accordance with the information provided in this report should limit
potential settlement to small fractions of an inch.
6.2.1 Lateral Load Parameters
Geotechnical parameters recommended for shaft design are presented in
the tables below. Many of these parameters are common among various
brands of commercial lateral load analysis software. Those shown are used
in the software program LPILE 2012®. If needed, other parameters not
shown will be provided upon request. We recommend that the lateral
resistance parameters be neglected for the uppermost 2 feet of shaft to
account for seasonal and annual cyclic variations in soil desiccation and
contraction. Tables 4 through 6 below describe stratigraphic sections for the
soils and rock encountered at the site.
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Table 4. Representative Soil Stratigraphy
Stratum Depth
Range (ft.)
Software Material
Designation
Effective Unit
Weight (pcf)
CLAY, dark brown, light
brown 0.0 – 10 Stiff Clay w/o Free
Water 120
SHALE, weathered, brown
and gray 10 – 20 Stiff Clay w/o Free
Water 125
SHALE, dark gray 20+ Weak Rock 130
Table 5. Recommended Geotechnical Parameters – Soil & Weathered Shale
Boring Material Software Material
Designation
Undrained
Cohesion (psf)
Friction
Angle
Strain
Factor,
ε50
CLAY, dark brown, light
brown
Stiff Clay w/o Free
Water 1,600 NA 0.01
SHALE, weathered Stiff Clay w/o Free
Water 5,600 NA 0.01
Table 6. Recommended Geotechnical Parameters – Shale
Boring Material Software Material
Designation
Unconfined
Compressive
Strength – (psi)
Modulus
(psi) RQD
Strain
Factor,
krm (rock)
SHALE, dark gray Weak Rock 115 10,000 90 0.003
In view of the nature and characteristics of the materials present, we
recommend that the lateral resistance parameters be neglected for the
uppermost 2 feet of soil materials to account for seasonal and annual cyclic
variations in soil desiccation and contraction, and potential future erosion.
However, unit weight in this zone can be considered in design, and the
lateral loads may be resolved at the top of the ground surface.
6.2.2 Drilled Shaft Construction Considerations
Groundwater seepage was generally not encountered during drilling and
prior to the introduction of water used for coring purposes. Groundwater
seepage during drilling was encountered in Borings B19 and B21 at depths
of 9 and 7 feet respectively but was dry at completion. Groundwater was not
encountered in Borings B13 and B20. The following day, groundwater was
generally observed at depths of 4 to 20 feet below the existing ground
surface. If the rate of groundwater seepage precludes use of conventional
pumps, temporary casing will be required. If needed due to excessive
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groundwater seepage, or if sloughing of overburden soils is observed,
temporary casing should be installed to a sufficient depth to obtain an
adequate seal against sloughing or groundwater. After the satisfactory
installation of the temporary casing, the required penetration into the
bearing material may be excavated by conventional means through the
casing.
The installation of all drilled piers should be observed by experienced
geotechnical personnel during construction to verify compliance with design
assumptions including: 1) verticality of the shaft excavation, 2) identification
of the bearing stratum, 3) minimum pier diameter and depth, 4) correct
reinforcement is placed, 5) proper removal of loose spoil, and 6) proper
handling of groundwater, if encountered. D&S would be pleased to provide
these services in support of this project.
During construction of the drilled shafts, care should be taken to avoid
creating an oversized cap ("mushroom") in excess of the shaft diameter,
particularly near the ground surface, that could allow expansive soils to
heave against. If near surface soils are prone to sloughing and “mushroom”
formation, the tops of the shafts should be formed above the depth of
sloughing using cardboard or other circular forms equal to the diameter of
the shaft.
Concrete used for the shafts should have a slump of 8 inches ± 1. Individual
shafts should be excavated in a continuous operation and concrete placed
as soon as practical after completion of the drilling. All pier holes should be
filled with concrete within 8 hours after completion of drilling. In the event
of equipment breakdown, any uncompleted open shaft should be backfilled
with soil to be redrilled at a later date. Backfilled shafts that have reached
the target depth prior to the delay and then backfilled should be extended a
minimum of 2 feet deeper than the original target depth. However, in such
cases this office should be notified to evaluate individual situations.
EARTHWORK RECOMMENDATIONS
In order to reduce Potential Vertical Movements to less than one-inch for soil-supported
equipment pads and other elements, we have the following recommendations for
subgrade preparation for the substation.
7.1 Subgrade Modifications
Strip the site of all vegetation and remove any remaining organic or deleterious
material, including all tree stumps and root balls of existing trees under areas
that will be covered with structures and pavements.
After stripping the site, perform any required cuts
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After excavating, and prior to the placement of any grade-raise fill across non-
paved areas, scarify, rework, and recompact the upper 12 inches of the
exposed subgrade soils. The soils should be compacted to between 93 and
98 percent of the maximum density as determined by ASTM D 698 (Standard
Proctor), and to at least plus three (+3) percentage points above its optimum
moisture content.
Grade raise fill should be placed in layer-compacted lifts not exceeding 8
inches in compacted thickness. These fills should be compacted to between
93 and 98 percent of the maximum density as determined by ASTM D 698
(Standard Proctor), and to at least plus three (+3) percentage points above its
optimum moisture content.
After the overall site has been brought to grade, excavate equipment pad areas
to a minimum depth of four (4) feet below the bottom of mat foundations (7 feet
below final exterior grade), or to the top of tan limestone if encountered during
the excavation process. The excavated materials may be stockpiled for
possible future reuse. Excavations should extend at least to the exterior mat
dimensions and then extend up to the ground surface at a slope no steeper
than 1:Horizontal to 1:Vertical.
Place geogrid across bottom and up the sides of the pad excavations to at least
the bottom of mat elevation. Geogrid may be either Tensar BX-1100, Tensar
Triax 160, or approved equivalent.
Place the stockpiled excavated soil to the bottom of mat footing elevation in
maximum 8-inch thick compacted lifts. Continue placing the reworked soil to a
depth of 1 foot below the bottom of the foundation. The reworked on-site fill
should be compacted to between 93 and 98 percent of the maximum density
as determined by ASTM D 698 (Standard Proctor), and to at least plus three
(+3) percentage points above its optimum moisture content.
Place a minimum of 2 feet of select fill below the bottom of the mat footing
elevation. Select fill should have a liquid limit less than 35 and a plasticity index
between 6 and 18, should be essentially free of organic materials and particles
in excess of 4 inches in their maximum direction, and should have not less than
30 percent material passing a No. 200 mesh sieve. The select fill should be
placed in maximum 6-inch thick compacted lifts and compacted to at least 95
percent of the maximum Standard Proctor density and within three (-3 to +3)
percentage points of its optimum moisture content.
Alternatively, aggregate base meeting the gradation, plasticity, and durability
requirements of TxDOT Standard Specification Item 247, Type A or D, Grade
2 or better may be used in lieu of select fill materials. If used, these materials
should be placed in maximum 4-inch thick compacted lifts and should be
compacted to at least 95 percent of the maximum Standard Proctor density.
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Backfill around the equipment pad containment walls above the reworked on-
site soil, select fill, or aggregate base pad fill should be clay soils with a
Plasticity Index of at least 25.
Backfill should be placed in maximum 8-inch compacted lifts and should be
compacted to a minimum of 95 percent of the maximum density as determined
by ASTM D 698 (Standard Proctor), and to its optimum moisture content or
above.
Each lift of fill or backfill should be tested for moisture content and compaction
by a testing laboratory at the rate of 1 test every 3,000 square feet per lift, with
a minimum of 3 tests per lift within each pad.
7.2 Additional Considerations
In order to minimize the potential for post-construction vertical movement,
consideration should be given to the following:
Final subgrade should slope away from the foundations to the maximum
degree possible, with a minimum of 5 percent in the first 5 feet, if practical.
Water should not be allowed to pond next to foundations.
PAVEMENTS
We understand that final site work will consist of either asphalt or gravel surfaces. Our
recommendations for pavements are presented in subsequent paragraphs.
8.1 General
The pavement designs given in this report are based upon the geotechnical
information developed during this study and design criteria assumptions based on
conversations with Denton Municipal Electric personnel and the design team. The
pavement designs shown below were produced considering the pavement design
practices for flexible pavements, the guidelines and recommendations of the
American Concrete Pavement Association (ACPA) as well as our experience and
professional opinion. However, the Civil Engineer-of-Record should produce the final
pavement design and all associated specifications for the project.
8.2 Behavior Characteristics of Expansive Soils Beneath Pavement
The near surface soils for this site are moderately expansive. These soils and have
the potential for volume change with changes in soil moisture content. The moisture
content can be maintained to some degree in these soils by covering them with an
impermeable surface such as pavement areas. However, if moisture is introduced to
the subgrade soils by surface or subsurface water, poor drainage, addition of
excessive rainfall after periods of no moisture, or removed by desiccation, the soils
can swell or shrink significantly, resulting in distress to pavements in contact with the
soil in the form of cracks and displacements. The edges of pavements are particularly
D&S ENGINEERING LABS, LLC Jim Christal Substation and Transmission Towers
Denton, Texas (13-0278-19)
14
prone to moisture variations, and these areas often experience the most distress
(cracking).
In order to minimize the negative impacts of expansive soil on pavement areas and
improve the long term performance of the pavement, we have the following
recommendations:
Provide a crowned or sloped pavement to quickly shed water off the pavement
surface.
Provide the maximum practical drainage away from the pavement. A minimum
of 5% slope for the first 5 feet is considered ideal.
Avoid long areas of low slope roadway. Adjust slopes to account for the
Potential Vertical Movement.
8.3 Subgrade Strength Characteristics
Based on the testing from the investigation and support characteristics after
performing the recommended subgrade soil preparation, we recommend using a
California Bearing Ratio (CBR) value of 3.5 for the on-site dark brown clay soils for
the pavement section design. A corresponding resilient modulus of 4,500 psi may
also be used for the dark brown clays. We also recommend a Modulus of Subgrade
Reaction (k) of 85 pounds per cubic inch (pci) for the subgrade soils (300 pci if
pavement is placed over aggregate base).
As the shear strength of soil is inversely related to the soil moisture content, we
recommend using an undrained shear strength of 1,600 psf for reworked soils
prepared as recommended herein, and when the site is graded properly to preclude
water from ponding at pavement edges.
8.4 Flexible Pavement Design and Recommendations
If utilized for this project, hot mix asphaltic concrete (HMAC) pavement should
conform to current TxDOT standards. The following subparagraphs provide
recommendations for HMAC. Actual loading conditions may require modifications.
8.4.1 Full Depth HMAC
Full-depth HMAC should consist of at least 2 inches of Type C or D surface
course over 4 inches of Type B base course as specified by TxDOT. The
full-depth asphalt should be placed over a minimum of 8 inches of lime
treated subgrade soil, or 6 inches of aggregate base.
8.4.2 Soil Preparation for Flexible Pavements – Lime Treatment
Strip the site of all vegetation to a minimum depth of 6 inches below
existing grades and remove any remaining organic or deleterious
material under the planned paved areas, including all tree stumps and
root balls of existing trees.
D&S ENGINEERING LABS, LLC Jim Christal Substation and Transmission Towers
Denton, Texas (13-0278-19)
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Cut or fill as needed to required pavement subgrade elevation. In areas
to receive fill, the fill should be placed in maximum 6-inch compacted lifts,
compacted to at least 95 percent of the maximum dry density, as
determined by ASTM D 698 (standard Proctor), and placed at a moisture
content that is at least two percentage points above the optimum
moisture content, as determined by the same test (≥+2%). Fill materials
may be derived from on-site or may be imported as long as the materials
are essentially free of organic materials and particles in excess of 4
inches their maximum direction. Imported fill material should have no less
than 35 percent material passing a No. 200 mesh sieve and a Plasticity
Index of no more than 30.
Mix lime slurry into the prepared subgrade soil after scarifying to a depth
of at least 8 inches. We estimate that a treated subgrade with a minimum
of 6 percent lime by dry weight measure (about 40 pounds of lime per
square yard of treated area) will be required. The actual amount of lime
should be determined by the testing lab once rough grading is complete.
The hydrated lime should be applied only in an area where the initial
mixing operations can be completed the same working day. The area of
lime treated subgrade should extend a minimum of 18-inches beyond the
back of roadway curbs or edges.
The material and hydrated lime should be thoroughly mixed to obtain a
homogeneous, friable mixture free of clods or lumps larger than about
the size of a golf ball. After initial mixing, roll the mixed material with a
suitable type and size of equipment in order to “seal-in” moisture and
minimize moisture loss. The rolled subgrade should be left to cure from
one to four days. During the curing period, the material should be kept
moist. To that end, in no case should the subgrade surface be allowed to
dry for more than 12 hours between instances of surface moistening /
wetting.
After the curing period, the subgrade should be thoroughly re-mixed to a
depth of 8 inches until the following gradational characteristics are
achieved (after the removal of non-slaking particles such as limestone,
concrete and/or asphalt fragments):
o Minimum passing 1-3/4 inch sieve = 100%
o Minimum passing no. 4 sieve = 60%
After achieving the required gradation, the treated soil-lime mixture
should then be immediately compacted to at least 95 percent of the
maximum dry density, as determined by ASTM D 698 (standard Proctor),
at placed at a moisture content that is at or above the optimum moisture
content, as determined by the same test.
D&S ENGINEERING LABS, LLC Jim Christal Substation and Transmission Towers
Denton, Texas (13-0278-19)
16
Water should not be allowed to pond on the treated surface. To that end,
the lime-treated subgrade surface should be shaped in a way that will
allow water to shed from one or more edges of the prepared subgrade.
Field density and moisture content testing should be performed at the
rate of one test per 10,000 square feet in pavement areas whose planned
use will principally consist of personal vehicles, and one test per 100
linear feet in utility trenches. For fire lanes and areas that will be subjected
to heavy vehicular traffic, the rate of testing should be increased to one
test performed per 5,000 square feet.
8.4.3 Aggregate Base
As an alternative to lime treatment, aggregate base may be placed over the
prepared subgrade in accordance with the following recommendations prior
to placing the pavement.
After stripping the site and prior to the placement of aggregate base, the
exposed subgrade beneath pavement areas should be scarified and
reworked to a depth of 12 inches, moisture added or removed as
required, and the subgrade soils recompacted to a minimum of 95
percent of the maximum dry density of the materials obtained in
accordance with ASTM D 698 (standard Proctor test) and to at least two
percentage points above the material’s optimum moisture content (≥ 2%).
The rework should extend to at least 18-inches beyond the outside edges
of curbs.
Within 24 hours of subgrade rework, begin fill operations as required to
final grade elevation. The fill soil should be placed in maximum 8-inch
loose lifts and be compacted to a minimum of 95 percent of the maximum
dry density of the materials obtained in accordance with ASTM D 698
(standard Proctor test) and to at least two percentage points above the
material’s optimum moisture content (≥ 2%).
After completing the subgrade preparation, place a minimum 6-inch thick
aggregate base layer. The area of aggregate base should extend a
minimum of 18-inches beyond the back of roadway curbs or edges of
pavement.
Aggregate base should be TxDOT Type A and meet the gradation,
durability and plasticity requirements of TxDOT Item 247 Grade 1.
Aggregate base material should be uniformly compacted to a minimum
of 95% of the maximum standard Proctor dry density (ASTM D 698) and
placed at a moisture content that is sufficient to achieve density.
8.5 All-weather Roads and Parking
For all-weather surfaces, we have the following recommendations:
D&S ENGINEERING LABS, LLC Jim Christal Substation and Transmission Towers
Denton, Texas (13-0278-19)
17
Prepare the subgrade similar to that described above for lime treatment.
Place a minimum of 10-inches of aggregate base. Aggregate base, should be
TxDOT Type A and meeting the gradation, durability and plasticity
requirements of TxDOT Item 247 Grade 1. Aggregate base material should be
uniformly compacted to a minimum of 95% of the maximum standard Proctor
dry density (ASTM D 698) and placed at a moisture content that is sufficient to
achieve density.
Place a minimum 2-inch thick surface course of clean durable gravel or
crushed stone over the compacted aggregate base surface. Suitable surface
course materials may include ASTM C 33 Types 3, 4, 5 or other similar coarse
gravel or crushed stone.
Field density and moisture content testing should be performed at the rate of
one test per 10,000 square feet in parking areas whose planned use will
principally consist of personal vehicles and one test per 100 linear feet in utility
trenches. For fire lanes and areas that will be subjected to heavy vehicular
traffic, the rate of testing should be increased to one test performed per 5,000
square feet.
8.6 Non-Paved Areas
We understand that non-paved areas within the substation footprint will receive
about 12 inches of crushed stone over the prepared subgrade. For these
areas, we recommend the following:
After the site has been brought to grade in accordance with the Earthwork
Section of this report, place a geotextile “filer fabric” between the subgrade soil
and the crushed stone to prevent soil migration into the stone
Place 12 inches of crushed stone around the paved areas as shown on the
plans.
Crushed stone should be a clean material conforming to ASTM C 33 with
particle sizes meeting materials size No. 57 or larger, or other similar coarse
gravel or crushed stone.
SEISMIC CONSIDERATIONS
North central Texas is generally regarded as an area of low seismic activity. Based on
the data developed, and considering the geologic conditions present, we recommend that
IBC Soil Site Class “C” be used at this site. The acceleration values below were
interpolated from published U.S. Geological Survey National Seismic Hazard Maps.
D&S ENGINEERING LABS, LLC Jim Christal Substation and Transmission Towers
Denton, Texas (13-0278-19)
18
Table 7. Seismic Design Parameters
Design Parameters Values
Site Class C
Spectral Acceleration for 0.2 sec Period, Ss (g) 0.111
Spectral Acceleration for 1.0 sec Period, S1 (g) 0.054
Site Coefficient for 0.2 sec Period, Fa 1.2
Site Coefficient for 1.0 sec Period, Fv 1.7
LIMITATIONS
The professional geotechnical engineering services performed for this project, the findings
obtained, and the recommendations prepared were accomplished in accordance with
currently accepted geotechnical engineering principles and practices.
Variations in the subsurface conditions are noted at the specific boring locations for this
study. As such, all users of this report should be aware that differences in depths and
thicknesses of strata encountered can vary between the boring locations. The number and
spacing of the exploration borings were chosen to obtain geotechnical information for the
design and construction of lightly to moderately--loaded structure foundations.
Statements in the report as to subsurface conditions across the site are extrapolated from
the data obtained at the specific boring locations. If there are any conditions differing
significantly from those described herein, D&S should be notified to re-evaluate the
recommendations contained in this report.
Recommendations contained herein are not considered applicable for an indefinite period
of time. Our office must be contacted to re-evaluate the contents of this report if
construction does not begin within a one-year period after completion of this report.
The scope of services provided herein does not include an environmental assessment of
the site or investigation for the presence or absence of hazardous materials in the soil,
surface water, or groundwater.
All contractors referring to this geotechnical report should draw their own conclusions
regarding excavations, construction, etc. for bidding purposes. D&S is not responsible for
conclusions, opinions or recommendations made by others based on these data. The
report is intended to guide preparation of project specifications and should not be used as
a substitute for the project specifications.
Recommendations provided in this report are based on our understanding of information
provided by the Client to us regarding the scope of work for this project. If the Client notes
any differences, our office should be contacted immediately since this may materially alter
the recommendations.
APPENDIX A - BORING LOGS AND SUPPORTING DATA
KEY TO SYMBOLS AND TERMS
CONSISTENCY: FINE GRAINED SOILS
CONDITION OF SOILS
SECONDARY COMPONENTS
WEATHERING OF ROCK MASS
TCP (#blows/ft)
< 8
8 - 20
20 - 60
60 - 100
> 100
Relative Density (%)
0 - 15
15 - 35
35 - 65
65 - 85
85 - 100
SPT (# blows/ft)
0 - 2
3 - 4
5 - 8
9 - 15
16 - 30
> 30
UCS (tsf)
< 0.25
0.25 - 0.5
0.5 - 1.0
1.0 - 2.0
2.0 - 4.0
> 4.0
CONSISTENCY OF SOILSLITHOLOGIC SYMBOLS
CONDITION: COARSE GRAINED SOILS
QUANTITY DESCRIPTORS
RELATIVE HARDNESS OF ROCK MASS
SPT (# blows/ft)
0 - 4
5 - 10
11 - 30
31 - 50
> 50
Description
No visible sign of weathering
Penetrative weathering on open discontinuity surfaces,
but only slight weathering of rock material
Weathering extends throughout rock mass, but the rock
material is not friable
Weathering extends throughout rock mass, and the rock
material is partly friable
Rock is wholly decomposed and in a friable condition but
the rock texture and structure are preserved
A soil material with the original texture, structure, and
mineralogy of the rock completely destroyed
Designation
Fresh
Slightly weathered
Moderately weathered
Highly weathered
Completely weathered
Residual Soil
Description
Can be carved with a knife. Can be excavated readily with
point of pick. Pieces 1" or more in thickness can be broken
by finger pressure. Readily scratched with fingernail.
Can be gouged or grooved readily with knife or pick point.
Can be excavated in chips to pieces several inches in size
by moderate blows with the pick point. Small, thin pieces
can be broken by finger pressure.
Can be grooved or gouged 1/4" deep by firm pressure on
knife or pick point. Can be excavated in small chips to
pieces about 1" maximum size by hard blows with the point
of a pick.
Can be scratched with knife or pick. Gouges or grooves 1/4"
deep can be excavated by hard blow of the point of a pick.
Hand specimens can be detached by a moderate blow.
Can be scratched with knife or pick only with difficulty.
Hard blow of hammer required to detach a hand specimen.
Cannot be scratched with knife or sharp pick. Breaking of hand
specimens requires several hard blows from a hammer or pick.
Trace
Few
Little
Some
With
Designation
Very Soft
Soft
Medium Hard
Moderately Hard
Hard
Very Hard
< 5% of sample
5% to 10%
10% to 25%
25% to 35%
> 35%
Condition
Very Loose
Loose
Medium Dense
Dense
Very Dense
Consistency
Very Soft
Soft
Medium Stiff
Stiff
Very Stiff
HardARTIFICIALAsphalt
Aggregate Base
Concrete
Fill
SOILROCKLimestone
Mudstone
Shale
Sandstone
Weathered Limestone
Weathered Shale
Weathered Sandstone
CH: High Plasticity Clay
CL: Low Plasticity Clay
GP: Poorly-graded Gravel
GW: Well-graded Gravel
SC: Clayey Sand
SP: Poorly-graded Sand
SW: Well-graded Sand
!
"
!
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,-)'.$/'',01/' %2
3
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56/-7#$%&'%-%2/(%4)++$,-)
8%2#$%&'()$%*++$,-)
,-)'.$/'',01/' %2
,-)'.$/'',01/'%2
!
"9
9
"9
9
60 20 40
4,4
6,6
7,10
25,18
50=0.25"50=0.25"
50=3.0"50=3.5"
2.5
2.5
3.0
4.0
4.5+
4.5+
4.5+
104.2 2.9
30.4
28.6
27.0
24.3
21.3
17.9
23.9
14.8
12.0 ft
17.0 ft
20.0 ft
FAT CLAY (CH); stiff to very stiff;dark brown, brown; trace calcareous
LIMESTONE; weathered; moderately
hard; tan, light gray
SHALE; moderately weathered; verysoft; dark gray; fissile
SHALE; fresh; soft; dark gray; fissile
S
S
S
T
S
T
S
T
S
S
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B1
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MC(%)
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REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/30/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/30/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21549, W97.20942
PROJECT NUMBER: 13-0278-19
50=4.0"50=3.0"
50=2.0"50=3.25" 30.4 ft
SHALE; fresh; soft; dark gray; fissile
End of boring at 30.4'
Notes:
-seepage at 23 feet during drilling-water at 8.5 feet after 24 hours
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B1
PAGE 2 OF 2
MC(%)
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REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/30/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/30/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21549, W97.20942
PROJECT NUMBER: 13-0278-19
50 19 31
3,5
4,7
2,5
9,91=5.75"
35,29
14,13
0.5
1.75
1.25
3.25
4.5+
3.5
4.5+
113.8 5.5
27.5
27.1
26.1
16.9
21.7
20.2
18.7
4.5 ft
10.5 ft
17.0 ft
24.0 ft
FAT CLAY (CH); soft to very stiff;dark brown, brown; trace calcareous
nodules
FAT CLAY (CH); stiff to very stiff;orange-brown, gray; few calcareous
nodules; trace iron stains
LIMESTONE; weathered; soft; tan,light gray
SHALE; moderately weathered; verysoft; dark gray; fissile
SHALE; fresh; very soft to soft; darkgray; fissile
S
S
S
T
S
T
S
T
S
S
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B2
PAGE 1 OF 2
MC(%)
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REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/31/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/31/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21542, W97.21009
PROJECT NUMBER: 13-0278-19
50=6.0"50=2.5"
50=5.5"50=2.0" 30.6 ft
SHALE; fresh; very soft to soft; darkgray; fissile
End of boring at 30.6'
Notes:-dry during drilling
-water at 7.5 feet after 24 hours
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B2
PAGE 2 OF 2
MC(%)
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REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/31/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/31/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21542, W97.21009
PROJECT NUMBER: 13-0278-19
53
44
17
14
36
30
4,3
8,8
9,23
28,31
50=1.5"50=6.0"
43,57=4.0"
1.25
3.0
1.5
1.5
3.25
4.5+
97.7 4.1
29.0
26.4
23.5
25.5
20.6
20.6
5.5 ft
11.0 ft
18.0 ft
FAT CLAY (CH); medium stiff to stiff;dark brown; trace calcareous nodules
LEAN CLAY (CL); stiff to very stiff;
orange-brown, gray, dark brown; traceto few calcareous nodules; tracelimestone fragments
LIMESTONE; weathered; soft; tan,light gray
SHALE; slightly to moderately
weathered; very soft; dark gray; fissile
S
S
S
T
S
T
S
T
S
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B3
PAGE 1 OF 2
MC(%)
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REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/1/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/1/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21521, W97.21066
PROJECT NUMBER: 13-0278-19
50=5.0"50=7.0"
50=3.25"50=1.0"
27.0 ft
30.3 ft
SHALE; slightly to moderatelyweathered; very soft; dark gray; fissile
SHALE; fresh; soft; dark gray; fissile
End of boring at 30.3'
Notes:-dry during drilling-water at 7.5 feet after 24 hours
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B3
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/1/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/1/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21521, W97.21066
PROJECT NUMBER: 13-0278-19
55 17 38
4,4
10,10
9,8
20,23
17,19
1.75
2.0
1.75
3.0
4.5+
4.5+
4.5+
4.5+
103.1 4.0
27.3
26.3
25.2
22.2
17.0
16.9
19.8
6.0 ft
11.0 ft
13.0 ft
FAT CLAY (CH); stiff; dark brown,brown; trace calcareous nodules
FAT CLAY (CH); very stiff;orange-brown, gray, brown; trace to
little calcareous nodules and ironstains; few limestone fragments and
fine gravel
LIMESTONE; weathered; soft; tan,light gray
SHALE; moderately to highlyweathered; very soft; gray,olive-green; fissile; trace iron stains
S
S
S
T
S
T
S
T
S
S
T
T
S
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B4
PAGE 1 OF 2
MC(%)
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REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/31/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/31/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21498, W97.21012
PROJECT NUMBER: 13-0278-19
43,57=3.0"
50=3.25"50=2.0"
27.0 ft
30.4 ft
SHALE; moderately to highlyweathered; very soft; gray,
olive-green; fissile; trace iron stains
SHALE; fresh; soft; dark gray; fissile
End of boring at 30.4'
Notes:
-dry during drilling-water at 7 feet after 24 hours
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B4
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/31/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/31/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21498, W97.21012
PROJECT NUMBER: 13-0278-19
58 18 40
4,4
4,5
10,10
8,12
50=1.75"50=0.25"
43,57
1.25
1.5
1.25
1.5
4.5+
4.5+
2.25
95.7 2.2
28.4
23.1
26.6
18.7
19.7
5.0 ft
11.0 ft
15.5 ft
FAT CLAY (CH); medium stiff; darkbrown; trace calcareous nodules
FAT CLAY (CH); stiff to very stiff;orange-brown, gray; few calcareousnodules; trace iron stains
LIMESTONE; weathered; moderatelyhard; tan, light gray
SHALE; moderately weathered; verysoft; dark gray; fissile
S
S
S
T
S
T
S
T
S
S
T
T
S
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B5
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 8/31/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/31/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21518, W97.20972
PROJECT NUMBER: 13-0278-19
45,55=4.0"
50=3.0"50=1.5"
27.0 ft
30.3 ft
SHALE; moderately weathered; verysoft; dark gray; fissile
SHALE; fresh; soft; dark gray; fissile
End of boring at 30.3'
Notes:-dry during drilling-water at 8 feet after 24 hours
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B5
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 8/31/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/31/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21518, W97.20972
PROJECT NUMBER: 13-0278-19
54
44
19
14
35
30
3,5
3,3
6,9
13,18
50=2.0"
50=0.25"
50=5.0"50=6.75"
106.7 5.9
29.9
26.5
21.3
18.9
21.9
17.0
5.0 ft
12.0 ft
16.0 ft
24.0 ft
FAT CLAY (CH); stiff to stiff; darkbrown; trace calcareous nodules
LEAN CLAY (CL); stiff to very stiff;orange-brown, light gray, dark brown;trace to few calcareous nodules; trace
limestone fragments
LIMESTONE; weathered; moderately
hard; tan, light gray
SHALE; moderately weathered; very
soft; dark gray; fissile
SHALE; fresh; soft; dark gray; fissile
S
S
S
T
S
T
S
T
S
S
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B6
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 8/30/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/30/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21478, W97.20939
PROJECT NUMBER: 13-0278-19
50=5.0"50=3.5"
50=3.5"50=2.0"
30.3 ft
SHALE; fresh; soft; dark gray; fissile
End of boring at 30.3'
Notes:-dry during drilling-water at 10 feet after 24 hours
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B6
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 8/30/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/30/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21478, W97.20939
PROJECT NUMBER: 13-0278-19
2.052
54
19
18
33
36
3,4
6,8
17,45
11,89=3.5"
22,46
50=6.0"
50=5.5"
3.5
3.5
3.5
3.5
4.5+
4.5+
4.5+
634.5 ft
631.5 ft
627.5 ft
621.0 ft
102.4
27.4
27.8
23.9
24.3
18.5
15.0
15.9
7.5 ft
10.5 ft
14.5 ft
21.0 ft
FAT CLAY (CH); very stiff; darkbrown, light brown; trace calcareous
nodules, limestone fragments, andfine gravel
LIMESTONE; very soft; highly
weathered; tan; highly argillaceous
LIMESTONE; weathered; soft; tan,gray; fossileferous
SHALE; moderately weathered; very
soft to soft; brown, gray; fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
S
S
S
T
S
T
S
T
S
S
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B7
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 8/9/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/9/2016
GROUND ELEVATION: Approx. 642 feet
GPS COORDINATES: N33.21478, W97.20939
PROJECT NUMBER: 13-0278-19
607.0 ft
124.0
119.0
20.6
12.4
13.7
16.8
35.0 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 35.0'
Notes:-dry until the introduction of water at
25 feet for coring purposes-water at 7 feet after 24 hours
100100
100100
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B7
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 8/9/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/9/2016
GROUND ELEVATION: Approx. 642 feet
GPS COORDINATES: N33.21478, W97.20939
PROJECT NUMBER: 13-0278-19
0.4511833
3,5
5,8
8,13
50=1.0"50=0.25"
40,60=4.5"
22,48
3.0
3.5
2.5
3.5
4.5+
4.5+
4.5+
94.8
103.3
2.0
24.5
26.0
26.3
23.6
18.7
17.3
20.5
6.0 ft
10.0 ft
13.0 ft
21.0 ft
FAT CLAY (CH); very stiff; darkbrown, light brown; trace calcareous
nodules and limestone fragments
LIMESTONE; highly to completelyweathered; very soft; tan, brown
LIMESTONE; weathered; moderately
hard; tan, gray; fossileferous
SHALE; moderately weathered; verysoft to soft; brown, gray; fissile
SHALE; fresh; soft to medium hard;dark gray; trace very thin limestoneseams; fissile
S
S
S
T
S
T
S
T
S
S
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B8
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/6/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/6/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21523, W97.21122
PROJECT NUMBER: 13-0278-19
50=3.0"
50=5.0"
50=2.25"50=2.0"
50=3.5"50=2.5"
50=2.75"
50=1.0"
40.3 ft
SHALE; fresh; soft to medium hard;dark gray; trace very thin limestone
seams; fissile
End of boring at 40.3'
Notes:-dry during drilling
-water at 20 feet after 24 hours
T
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B8
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/6/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/6/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21523, W97.21122
PROJECT NUMBER: 13-0278-19
52 18 34
2,3
5,7
6,10
50=6.0"50=3.0"
10,14
3.5
3.5
3.5
2.0
4.5+
4.5+
3.5
4.5+
4.5+
107.9 5.5
25.4
23.1
28.9
27.4
19.8
19.8
10.0 ft
12.0 ft
22.0 ft
FAT CLAY (CH); stiff to very stiff;dark brown, brown; trace calcareous
nodules and limestone fragments
LIMESTONE; weathered; soft; tan,
gray
SHALE; moderately to highly
weathered; very soft; brown, gray;fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
S
S
S
T
S
T
S
T
S
S
T
S
T
S
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B9
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/6/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/6/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21433, W97.21120
PROJECT NUMBER: 13-0278-19
50=4.5"50=1.5"
50=4.5"50=1.75"
50=3.0"50=2.0"
50=2.25"
50=2.0"
40.3 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 40.3'
Notes:-dry during drilling
-water at 7 feet after 24 hours
T
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B9
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/6/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/6/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21433, W97.21120
PROJECT NUMBER: 13-0278-19
2.150
34
16
13
34
21
8,8
8,10
7,8
50=1.5"50=0.5"
43,45
4.5+
3.5
4.5+
2.0
3.5
1.5
106.5
26.1
20.6
21.3
18.1
17.9
18.7
5.5 ft
9.0 ft
13.5 ft
20.0 ft
FAT CLAY (CH); stiff to very stiff;dark brown; few calcareous nodules
LEAN CLAY (CL); medium stiff to
very stiff; light brown; few calcareousnodules
LIMESTONE; weathered; moderatelyhard; tan, gray
SHALE; highly to moderatelyweathered; very soft; brown, gray;fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
10080
S
S
S
T
S
T
S
T
S
T
T
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B10
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 9/19/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/20/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21491, W97.21165
PROJECT NUMBER: 13-0278-19
14.4
30.0 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 30.0'
Notes:
-dry until the introduction of water at20 feet for coring purposes-water at 20 feet after 24 hours
10084C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B10
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 9/19/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/20/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21491, W97.21165
PROJECT NUMBER: 13-0278-19
3.8531637
4,5
6,7
7,16
10,13
7,13
1.5
2.0
3.0
3.5
1.5
2.5
110.3
24.5
28.1
19.9
23.9
25.2
20.6
15.4
8.5 ft
10.0 ft
20.0 ft
FAT CLAY (CH); medium stiff to verystiff; dark brown, light brown; few
calcareous nodules and limestonefragments
LIMESTONE; weathered; soft; tan
SHALE; highly to moderately
weathered; very soft; brown, gray;fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
9292
S
S
S
T
S
T
S
T
S
T
T
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B11
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/20/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/20/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21420, W97.21165
PROJECT NUMBER: 13-0278-19
50=3.0"50=2.0" 30.4 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 30.4'
Notes:
-dry until the introduction of water at20 feet for coring purposes-water at 20 feet after 24 hours
6464C
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B11
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/20/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/20/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21420, W97.21165
PROJECT NUMBER: 13-0278-19
52 16 36
7,8
50=0.5"
50=0.5"
11,21
50=5.0"50=3.0"
2.5
2.5
4.5+
4.5+
634.0 ft
631.0 ft
627.0 ft
619.0 ft
21.4
25.0
21.1
20.1
16.4
5.0 ft
8.0 ft
12.0 ft
20.0 ft
FAT CLAY (CH); stiff to very stiff;dark brown, brown; trace calcareous
nodules and limestone fragments
LIMESTONE; weathered; moderatelyhard; tan, gray; fossiliferous
SHALE; highly weathered; very soft;brown; fissile
SHALE; slightly to moderately
weathered; soft; gray, dark gray; fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
9696
S
S
S
T
S
T
T
T
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B12
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 9/13/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/19/2016
GROUND ELEVATION: Approx. 639 feet
GPS COORDINATES: N33.21535, W97.21201
PROJECT NUMBER: 13-0278-19
599.0 ft
18.0
24.4
40.0 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 40.0'
Notes:-dry until the introduction of water at20 feet for coring purposes
-water at 20 feet after 24 hours
100100
100100
92
92
C
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B12
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Miles Sorbel (D&S)
START DATE: 9/13/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/19/2016
GROUND ELEVATION: Approx. 639 feet
GPS COORDINATES: N33.21535, W97.21201
PROJECT NUMBER: 13-0278-19
1.1521537
4,5
50=4.0"50=0.25"
11,21
50=5.75"50=3.0"
50=4.75"
50=3.0"
3.0
3.0
3.0
3.5
634.0 ft
630.5 ft
623.5 ft
94.3
95.8 1.9
18.9
21.4
25.3
27.4
5.0 ft
8.5 ft
15.5 ft
FAT CLAY (CH); stiff to very stiff;dark brown; trace calcareous nodules,
ferrous nodules and limestonefragments
LIMESTONE; weathered; soft tomoderately hard; tan, gray;fossiliferous
SHALE; highly to moderatleyweathered; very soft; brown, gray;
fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
S
S
S
T
S
T
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B13
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/7/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/7/2016
GROUND ELEVATION: Approx. 639 feet
GPS COORDINATES: N33.21479, W97.21216
PROJECT NUMBER: 13-0278-19
43,50=3.5"
50=4.5"
50=3.75" 608.3 ft
30.7 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 30.7'
Notes:-dry during drilling-dry after 24 hours
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B13
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/7/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/7/2016
GROUND ELEVATION: Approx. 639 feet
GPS COORDINATES: N33.21479, W97.21216
PROJECT NUMBER: 13-0278-19
50 17 33
4,4
50=1.0"
50=0.25"
14,20
32,68=3.5"
50=3.0"50=3.0"
4.0
2.5
3.5
3.5
102.5 3.6
20.8
25.3
23.8
25.2
9.8
5.0 ft
9.0 ft
15.5 ft
FAT CLAY (CH); stiff to very stiff;dark brown, light brown; trace
calcareous nodules and limestonefragments
LIMESTONE; weathered; moderatelyhard; tan, gray; fossiliferous
SHALE; highly to moderatelyweathered; very soft; brown, gray;fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
S
S
S
T
S
T
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B14
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/6/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/6/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21455, W97.21215
PROJECT NUMBER: 13-0278-19
50=3.0"
50=2.0"
50=4.5"50=2.0"
50=3.0"50=2.0"
50=2.0"
50=2.5"
40.3 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 40.3'
Notes:-dry during drilling
-water at 4 feet after 24 hours
T
T
T
T
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B14
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/6/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/6/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21455, W97.21215
PROJECT NUMBER: 13-0278-19
50 20 30
14,86=3.0"
12,31
22,40
36,64
4.0
4.5+
4.5+
119.0 14.0
22.4
24.4
25.5
15.1
3.5 ft
5.0 ft
15.5 ft
FAT CLAY (CH); very stiff; darkbrown; trace calcareous nodules and
ferrous nodules; few limestonefragments
LIMESTONE; weathered; soft to
medium hard; tan, gray; fossiliferous
SHALE; highly to moderatelyweathered; very soft; gray, brown;fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
100100
4444
S
S
S
T
T
T
T
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B15
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/7/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/7/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21503, W97.21246
PROJECT NUMBER: 13-0278-19
119.4 15.814.8
35.0 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 35.0'
Notes:-dry until the introduction of water at
16 feet for coring purposes-water at 7 feet after 24 hours
8888
9090
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B15
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/7/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/7/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21503, W97.21246
PROJECT NUMBER: 13-0278-19
1.7522329
50=4.0"
50=4.0"
50=1.5"50=1.5"
7,10
49,51=5.5"
4.0
4.5+
635.0 ft
630.5 ft
621.0 ft
102.1
120.1 9.8
19.7
21.9
14.9
2.0 ft
6.5 ft
16.0 ft
FAT CLAY (CH); very stiff; darkbrown; trace calcareous nodules,
ferrous nodules and fine gravel; fewlimestone fragments
LIMESTONE; weathered; soft tomoderately hard; tan, gray;
fossiliferous
SHALE; highly to moderatelyweathered; very soft; gray, brown;
fissile
SHALE; fresh; soft; dark gray; trace
very thin limestone seams; fissile
100100
S
S
T
T
T
T
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B16
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/8/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/8/2016
GROUND ELEVATION: Approx. 637 feet
GPS COORDINATES: N33.21434, W97.21245
PROJECT NUMBER: 13-0278-19
597.0 ft
114.4 13.815.3
40.0 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 40.0'
Notes:-dry until the introduction of water at20 feet for coring purposes
-water at 8 feet after 24 hours
100100
100100
100
100
C
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B16
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/8/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/8/2016
GROUND ELEVATION: Approx. 637 feet
GPS COORDINATES: N33.21434, W97.21245
PROJECT NUMBER: 13-0278-19
3.3
28
47
15
17
13
30
14,7
7,7
50=3.25"
50=2.0"
4.0
4.5+
3.0
4.5+
4.5+
108.6
18.9
8.9
20.8
21.3
23.5
16.9
1.0 ft
5.0 ft
10.0 ft
15.0 ft
FAT CLAY (CH); very stiff; darkbrown; trace calcareous nodules,
ferrous nodules and limestonefragments
LIMESTONE; weathered; very soft tosoft; tan, gray
SHALE; highly to completelyweathered; very soft; light gray, lightbrown; slightly fissile
SHALE; slightly to moderately
weathered; soft; brown, dark gray;fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
100100
100100
S
S
T
S
T
S
S
T
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B17
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/20/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/20/2016
GROUND ELEVATION:
GPS COORDINATES: N 33.21509, W97.21315
PROJECT NUMBER: 13-0278-19
16.3
35.0 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 35.0'
Notes:-dry until the introduction of water at
16 feet for coring purposes-water at 9.5 feet after 24 hours
100100
100100
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B17
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/20/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/20/2016
GROUND ELEVATION:
GPS COORDINATES: N 33.21509, W97.21315
PROJECT NUMBER: 13-0278-19
2.350
26
17
13
33
13
3,7
18,45
50=4.0"50=3.5"
25,38
45,55=6.0"
4.25
4.5+
2.5
2.5
3.0
108.3
22.5
19.0
12.9
16.9
11.7
18.4
2.0 ft
7.0 ft
9.5 ft
15.5 ft
FAT CLAY (CH); very stiff; darkbrown; trace calcareous nodules,
ferrous nodules and limestonefragments
LIMESTONE; highly to completelyweathered; very soft; tan
LIMESTONE; weathered; soft; tan,gray
SHALE; moderately to highly
weathered; very soft to soft; brown,gray; fissile
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
9898
9898
S
S
S
T
S
T
S
T
T
T
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B18
PAGE 1 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/21/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/21/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21424, W97.21309
PROJECT NUMBER: 13-0278-19
17.7
12.1
35.0 ft
SHALE; fresh; soft; dark gray; tracevery thin limestone seams; fissile
End of boring at 35.0'
Notes:-dry until the introduction of water at
16 feet for coring purposes-water at 9.5 feet after 24 hours
8080
9898
C
C
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
25
30
35
40
45
50
Atterberg Limits
Clay(%)
B18
PAGE 2 OF 2
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 9/21/2016 DRILL METHOD: CFA/Core
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 9/21/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21424, W97.21309
PROJECT NUMBER: 13-0278-19
62 20 42
3.5
3.5
3.5
3.5
3.5
4.5+
4.5+
4.0
4.0
4.5+
27.5
26.2
19.7
15.6
20.2
15.9
5.0 ft
10.0 ft
FAT CLAY WITH SAND (CH); verystiff; dark brown; trace calcareous
nodules
LIMESTONE; highly to completelyweathered; very soft; tan, brown
End of boring at 10.0'
Notes:-seepage at 9 feet during drilling
-dry at completion
S
S
S
S
S
S
S
S
S
S
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B19
PAGE 1 OF 1
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/30/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/30/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21634, W97.21147
PROJECT NUMBER: 13-0278-19
50 17 33
5,6,9
1.5
2.0
2.0
2.0
2.0
4.0
4.5+
4.5+
73
23.9
19.0
16.9
20.7
20.8
7.0 ft
10.0 ft
FAT CLAY WITH SAND (CH); verystiff; dark brown, brown; trace
calcareous nodules and fine gravel
LIMESTONE; highly to completelyweathered; very soft; tan, brown
End of boring at 10.0'
Notes:-dry during drilling
-dry at completion
S
S
S
S
S
N
S
S
S
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B20
PAGE 1 OF 1
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/30/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/30/2016
GROUND ELEVATION:
GPS COORDINATES: N33.21830, W97.21252
PROJECT NUMBER: 13-0278-19
61 20 41
2.0
2.0
2.0
2.0
2.0
2.0
2.0
4.5+
8426.2
24.5
16.2
16.9
26.9
7.0 ft
9.0 ft
10.0 ft
FAT CLAY WITH SAND (CH); verystiff; dark brown, brown; trace
calcareous nodules and fine gravel
LIMESTONE; highly weathered; verysoft; tan, brown
SHALE; highly weathered; very soft;light gray, brown; fissile
End of boring at 10.0'
Notes:-seepage at 7 feet during drilling
-dry at completion
S
S
S
S
S
S
S
S
Swell(%)LL(%)PL(%)PI
TotalSuction(pF)
Hand
Pen. (tsf)orSPT
orTCP
Hand
Pen. (tsf)orSPT
orTCP
Passing
#200Sieve
(%)
BORING LOG
GraphicLog DUW(pcf)
Unconf.Compr.Str (ksf)
Depth(ft)
0
5
10
15
20
25
Atterberg Limits
Clay(%)
B21
PAGE 1 OF 1
MC(%)
Legend: S-Shelby Tube N-Standard Penetration T-Texas Cone Penetration C-Core B-Bag Sample - Water Encountered
REC
(%)RQD
(%)
SampleType
CLIENT: Denton Municipal Electric
LOCATION: Denton, TXPROJECT: Jim Christal Substation
DRILLED BY: Kevin Kavadas (D&S)
START DATE: 8/30/2016 DRILL METHOD: Cont. Flight Auger
LOGGED BY: Ricky Ybarra (D&S)
FINISH DATE: 8/30/2016
GROUND ELEVATION:
GPS COORDINATES: N33.22035, W97.21201
PROJECT NUMBER: 13-0278-19
B10 2-3 21.3 22.8 390 2.1
B11 2-3 19.9 21.3 391 3.8
B13 2-3 25.3 27.4 391 1.1
B16 1-2 21.9 23.1 261 1.7
B17 7-8 21.3 24.0 1040 3.3
B18 1-2 19.0 20.3 260 2.3
B7 2-3 23.9 25.9 390 2.0
B8 4-5 23.6 25.1 658 0.4
Boring
Number Depth
feet
Applied Pressure,psf Vertical Swell, %
SWELL TEST RESULTS
Final Moisture
Content, %
Initial Moisture
Content, %
CLIENT: Denton Municipal ElectricPROJECT: Jim Christal Substation
PROJECT NUMBER: 13-0278-19 LOCATION: Denton, TX
APPENDIX B - GENERAL DESCRIPTION OF PROCEDURES
ANALYTICAL METHODS TO PREDICT MOVEMENT
CLASSIFICATION TESTS
Classification testing is perhaps the most basic, yet fundamental tool available for predicting
potential movements of clay soils. Classification testing typically consists of moisture content,
Atterberg Limits, and Grain-size distribution determinations. From these results a general
assessment of a soil’s propensity for volume change with changes in soil moisture content can
be made.
Moisture Content
By studying the moisture content of the soils at varying depths and comparing them with the
results of Atterberg Limits, one can estimate a rough order of magnitude of potential soil
movement at various moisture contents, as well as movements with moisture changes. These
tests are typically performed in accordance with ASTM D 2216.
Atterberg Limits
Atterberg limits determine the liquid limit (LL), plastic limit (PL), and plasticity index (PI) of a soil.
The liquid limit is the moisture content at which a soil begins to behave as a viscous fluid. The
plastic limit is the moisture content at which a soil becomes workable like putty, and at which a
clay soil begins to crumble when rolled into a thin thread (1/8” diameter). The PI is the numerical
difference between the moisture constants at the liquid limit and the plastic limit. This test is
typically performed in accordance with ASTM D 4318.
Clay mineralogy and the particle size influence the Atterberg Limits values, with certain minerals
(e.g., montmorillonite) and smaller particle sizes having higher PI values, and therefore higher
movement potential.
A soil with a PI below about 15 to 18 is considered to be generally stable and should not
experience significant movement with changes in moisture content. Soils with a PI above about
30 to 35 are considered to be highly active and may exhibit considerable movement with changes
in moisture content.
Fat clays with very high liquid limits, weakly cemented sandy clays, or silty clays are examples of
soils in which it can be difficult to predict movement from classification testing alone.
Grain-size Distribution
The simplest grain-size distribution test involves washing a soil specimen over the No. 200 mesh
sieve with an opening size of 0.075 mm (ASTM D 1140)). This particle size has been defined by
the engineering community as the demarcation between coarse-grained and fine-grained soils.
Particles smaller than this size can be further distinguished between silt-size and clay-size
particles by use of a Hydrometer test (ASTM D 422). A more complete grain-size distribution test
that uses sieves to relative amount of particles according is the Sieve Gradation Analysis of Soils
(ASTM D 6913). Once the characteristics of the soil are determined through classification testing,
a number of movement prediction techniques are available to predict the potential movement of
the soils. Some of these are discussed in general below.
TEXAS DEPARTMENT OF TRANSPORTATION METHOD 124-E
The Texas Department of Transportation (TxDOT) has developed a generally simplistic method
to predict movements for highways based on the plasticity index of the soil. The TxDOT method
is empirical and is based on the Atterberg limits and moisture content of the subsurface soil. This
method generally assumes three different initial moisture conditions: dry, “as-is”, and wet.
Computation of each over an assumed depth of seasonal moisture variation (usually about 15
feet or less) provides an estimate of potential movement at each initial condition. This method
requires a number of additional assumptions to develop a potential movement estimate. As such,
the predicted movements generally possess large uncertainties when applied to the analysis of
conditions under building slabs and foundations. In our opinion, estimates derived by this method
should not be used alone in determination of potential movement.
SUCTION
Suction measurements may be used along with other movement prediction methods to predict
soil movement. Suction is a measure of the ability of a soil to attract or lose moisture between the
soil particles. Since changes in soil moisture result in volume changes within the soil mass of fine-
grained soils (clays and to some degree silts), a knowledge of the suction potential of a soil mass
at a given point in time may be used to estimate potential future volume changes with changes in
soil moisture content. For this analysis, a series of suction measurements versus depth is typically
performed on a number of soil samples recovered from a boring in order to develop a suction
profile.
SWELL TESTS
Swell tests can lead to more accurate site specific predictions of potential vertical movement by
measuring actual swell volumes at in situ initial moisture contents. One-dimensional swell tests
are almost always performed for this measurement. Though swell is a three-dimensional process,
the one-dimensional test provides greatly improved potential vertical movement estimates than
other methods alone, particularly when the results are “weighted” with respect to depth, putting
more emphasis on the swell characteristics closer to the surface and less on values at depth.
POTENTIAL VERTICAL MOVEMENT
A general index for movement is known as the Potential Vertical Rise (PVR). The actual term
PVR refers to the TxDOT Method 124-E mentioned above. For the purpose of this report the term
Potential Vertical Movement (PVM) will be used since PVM estimates are derived using multiple
analytical techniques, not just TxDOT methods.
It should be noted that slabs and foundations constructed on clay or clayey soils may have at
least some risk of potential vertical movement due to changes in soil moisture contents. To
eliminate that risk, slabs and foundation elements may be designed as structural elements
physically separated by some distance from the subgrade soils (usually 4 to 12 inches).
In some cases, a floor slab with movements as little as 1/4 of an inch may result in damage to
interior walls, such as cracking in sheet rock or masonry walls, or separation of floor tiles.
However, these cracks are often minor and most people consider them 'liveable'. In other cases,
movement of one inch may cause significant damage, inconvenience, or even create a hazard
(trip hazard or others).
Vertical movement of clay soils under slab on grade foundations due to soil moisture changes
can result from a variety causes, including poor site grading and drainage, improperly prepared
subgrade, trees and large shrubbery located too close to structures, utility leaks or breaks, poor
subgrade maintenance such as inadequate or excessive irrigation, or other causes. The potential
for post-construction vertical movement can be minimized through adequate design, proper
construction, and adherence to the recommendations contained herein for post-construction
maintenance.
POTENTIAL VERTICAL MOVEMENT (PVM)
PVM is generally considered to be a measurement of the change in height of a foundation from
the elevation it was originally placed. Experience and generally accepted practice suggests that
if the PVM of a site is less than one inch, the associated differential movement will be minor and
acceptable to most people.
SETTLEMENT
Settlement is a measure of a downward movement due to consolidation of soil. This can occur
from improperly placed fill (uncompacted or under-compacted), loose native soil, or from large
amounts of unconfined sandy material. Properly compacted fill may settle approximately 1 percent
of its depth, particularly when fill depths exceed 10 feet.
EDGE AND CENTER LIFT MOVEMENT (ym)
The Post-Tensioning Institute (PTI) has developed a parameter of movement defined as the
differential movement (ym) estimated using the change in soil surface elevation in two locations
separated by a distance em within which the differential movement will occur; em being measured
from the exterior of a building to some distance toward the interior. All calculations for this report
are based on the modified PTI procedure in addition to our judgment as necessary for specific
site conditions. The minimum movements given in the PTI are for climatic conditions only and
have been modified somewhat to account for site conditions which may increase the actual
parameters.
“Center lift” occurs when the center, or some portion of the center of the building, is higher than
the exterior. This can occur when the soil around the exterior shrinks, or the soil under the center
of the building swells, or a combination of both occurs.
“Edge lift” occurs when the edge, or some portion of the exterior of the building, is higher than the
center. This can occur when the soil around the exterior swells. It is not uncommon to have both
the center lift and the edge lift phenomena occurring on the same building, in different areas.
SPECIAL COMMENTARY ON CONCRETE AND EARTHWORK
RESTRAINT TO SHRINKAGE CRACKS
One of the characteristics of concrete is that during the curing process shrinkage occurs and if
there are any restraints to prevent the concrete from shrinking, cracks can form. In a typical slab
on grade or structurally suspended foundation there will be cracks due to interior beams and piers
that restrict shrinkage. This restriction is called Restraint to Shrinkage (RTS). In post tensioned
slabs, the post tensioning strands are slack when installed and must be stressed at a later time.
The best procedure is to stress the cables approximately 30 percent within one to two days of
placing the concrete. Then the cables are stressed fully when the concrete reaches greater
strength, usually in 7 days. During this time before the cables are stressed fully, the concrete may
crack more than conventionally reinforced slabs. When the cables are stressed, some of the
cracks will pull together. These RTS cracks do not normally adversely affect the overall
performance of the foundation. It should be noted that for exposed floors, especially those that
will be painted, stained or stamped, these cracks may be aesthetically unacceptable. Any tile
which is applied directly to concrete or over a mortar bed over concrete has a high probability of
minor cracks occurring in the tile due to RTS. It is recommended if tile is used to install expansion
joints in appropriate locations to minimize these cracks.
UTILITY TRENCH EXCAVATION
Trench excavation for utilities should be sloped or braced in the interest of safety. Attention is
drawn to OSHA Safety and Health Standards (29 CFR 1926/1910), Subpart P, regarding trench
excavations greater than 5 feet in depth.
FIELD SUPERVISION AND DENSITY TESTING
Construction observation and testing by a field technician under the direction of a licensed
geotechnical engineer should be provided. Some adjustments in the test frequencies may be
required based upon the general fill types and soil conditions at the time of fill placement.
We recommend that all site and subgrade preparation, proof rolling, and pavement construction
be monitored by a qualified engineering firm. D&S would be pleased to provide these services in
support of this project. Density tests should be performed to verify proper compaction and
moisture content of any earthwork. Inspection should be performed prior to and during concrete
placement operations.
14805 Trinity Boulevard, Fort Worth, Texas 76155
Geotechnical 817.529.8464 Corporate 940.735.3733
www.dsenglabs.com
Texas Engineering Firm Registration # F‐12796
Oklahoma Engineering Firm Certificate of Authorization CA 7181