HomeMy WebLinkAboutRFP 8902 Scope of Work.Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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The respondent’s submission shall have accurately described your understanding of the objectives and scope
of the requested products and services and provided an outline of your process to implement the requirements
of the Scope of Work and Services. It is anticipated that the scope of work will include, at a minimum, the
following:
NORMAL WORKING HOURS
For this contract, normal working hours will be considered as 7:00 a.m. to 6:00 p.m. Monday through
Friday. Work outside the normal working hours, including Saturday and Sunday, or during restricted hours
as defined in the specification, shall not be permitted except with the written permission of the City of
Denton’s Project Manager. In addition, no work will be allowed on legal city holidays except with the
written permission of the Project Manager. Requests shall be made on a case-by-case basis in writing at
least 3 days in advance. The following is a list of the City’s legal holidays:
1. New Year’s Day (observed)
2. Martin Luther King, Jr. Day
3. Memorial Day
4. Juneteenth
5. Independence Day
6. Labor Day
7. Veteran’s Day
8. Thanksgiving Day
9. Friday After Thanksgiving
10. Christmas Eve (observed)
Maintain a center of operations and/or office with telephone or cell phone to support daily operations. This
center of operations shall be staged with capable personnel to manage ongoing operations in compliance
with the terms and conditions of this agreement. Responses to all calls within four hours are required during
working hours
THOROUGHFARES
The contractor shall not cause or allow interference with traffic flow on a thoroughfare during the hours of
6:30 am through 9:30 am, and 3:30 pm through 6:30 pm, Monday through Friday.
Contractor shall observe business-like conduct and etiquette at all times, treating all citizens with respect
regardless of race, age, or economic status.
STAGING AREA
The Contractor will be responsible for finding a suitable staging area. If available, City may provide a
designated staging area to the contractor. Contractor will not be allowed to store personal items in the Street
Department’s materials yard. The Contractor shall stage and organize their materials, equipment and trucks
in such a way that it doesn’t interfere with the Street Departments daily operations.
Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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If the successful respondent is unable to meet specifications on a daily basis due to equipment failure or
other delivery commitments, the City of Denton will have the option to obtain materials from the
secondary vendor. The Street Department needs the work completed within the time frames stated in
section next section.
Limitations.
All Micro-Surfacing will be applied between (April 1st and July 1st) and (September 1st November 15th)
unless otherwise approved by the Project Manager. This is contingent upon the weather conditions met
the requirements below.
POLYMER-MODIFIED EMULSIFIED ASPHALT SLURRY SEAL
SCOPE
The intent of this guideline is to aid in the design, testing, quality control, measurement and payment
procedures for the application of polymer-modified emulsified asphalt slurry seal.
DESCRIPTION
Polymer-modified emulsified asphalt slurry seal shall consist of a mixture of a polymer-modified emulsified
asphalt, mineral aggregate, water, and additives, proportioned, mixed and uniformly spread over a properly
prepared surface as directed by the Buyer's Authorized Representative (B.A.R.). The polymer-modified
emulsified asphalt slurry seal shall be applied in a single layer as a homogeneous mat, adhere firmly to the
prepared surface, and have a skid-resistant texture throughout its service life. This is not a product to be
utilized for reprofiling, leveling, or rut filling applications.
SPECIFICATIONS
It is not normally required to run all tests on every project. A compilation of results from the listed tests
should be indicative of system performance. Failure to meet specifications r an individual test does not
necessarily disqualify the system. If, for example, the system to be used on the project has a record of good
performance, individual requirements for testing may be waived. Test methods are listed in Appendix A
and form an integral part of this Guideline.
LABORATORY EVALUATION
Before work commences, the contractor shall submit a signed original of a mix design containing the test
results and proportioning of the specific materials to be used on the project. This design shall have been
performed by a qualified laboratory. Previous lab reports covering the exact materials to be used may be
accepted provided they were made during the calendar year. This initial mix design will be done at the
contractor’s expense. Upon receipt of the original mix design, an independent qualified laboratory selected
by the City of Denton will perform tests using the same materials as used in the initial mix design for
verification of the results. This testing will be done at City of Denton expense. No work will begin until all
Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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materials and/or mix design proportions have met the specifications as required. Once the materials are
approved, no substitutions will be permitted unless first tested and approved by the methods stated above.
APPLICABLE SPECIFICATIONS
The following specifications and test methods form a part of this specification.
AASHTO: American Association of State Highway and Transportation Officials
ASTM: American Society for Testing and Materials
ISSA: International Slurry Seal Association
MATERIALS
POLYMER-MODIFIED EMULSIFIED ASPHALT
GENERAL
The emulsified asphalt shall be polymer modified. The polymer material shall be milled or
blended into the asphalt or emulsifier solution prior to the emulsification process. While three
percent (3%) polymer solids, based on asphalt weight, is considered typical, other options may be
considered depending on project performance expectations.
Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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QUALITY TESTS APPENDIX A
The polymer-modified emulsified asphalt, and polymer-modified emulsified asphalt residue, shall
meet the requirements of AASHTO M 316, AASHTO M 208 or ASTM D 2397 for CQS-1h,
CQS-1hp, or CQS-1P, with the following exceptions:
1To prevent degradation of the polymer in polymer-modified emulsions, there are two options to
consider. Option No. 1 is to recover the residual asphalt by distillation at 350°F (177°C),
maintaining that temperature for 20 minutes. Option No. 2 is to recover the residual asphalt by
oven evaporation according to ASTM D6934 or AASHTO T 59.
NOTE: When results from the oven evaporation method fail to meet the specification
requirements, rerun the tests using residual asphalt obtained from 350°F distillation method.
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Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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Each load of emulsified asphalt shall be accompanied with a Certificate of
Compliance/Conformance or other documentation as defined in the Supplier Quality Acceptance
Plan to indicate that the emulsion meets the specifications.
AGGREGATE
GENERAL
The mineral aggregate used shall be the type specified for the particular application requirements
of the slurry seal. The aggregate shall be crushed stone such as granite, slag, limestone, chat, or
other high-quality aggregate, or combination thereof. To assure the material is 100 percent
crushed, the parent aggregate will be larger than the largest stone in the gradation to be used.
QUALITY TESTS
The aggregate should meet agency specified polishing values and these minimum requirements:
1The abrasion test is run on the parent aggregate.
GRADATION
When tested in accordance with AASHTO T 27 (ASTM C 136) and AASHTO T 11 (ASTM C
117), the mix design aggregate gradation shall be within one of the following bands (or one
recognized by the local paving authority):
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Roadway Surface Treatment Services
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The gradation of the aggregate stockpile shall not vary by more than the stockpile tolerance from
the mix design gradation (indicated in the table above) while also remaining within the
specification gradation band. The percentage of aggregate passing any two successive sieves shall
not change from one end of the specified range to the other end.
The aggregate will be accepted at the job location or stockpile based on five gradation tests
sampled according to AASHTO T 2 (ASTM D 75). If the average of the five tests is within the
stockpile tolerance from the mix design gradation, the material will be accepted. If the average of
those test results is out of specification or tolerance, the contractor will be given the choice to
either remove the material or blend additional aggregate with the stockpile material to bring it
into compliance. Materials used in blending must meet the required aggregate quality test
specifications in Section 4.2.2 before blending and must be blended in a manner to produce a
consistent gradation. Aggregate blending may require a new mix design.
Screening shall be required at the stockpile if there are any problems created by oversized
materials in the mix.
Type I. This aggregate gradation is used to fill surface voids, address moderate surface distresses,
and provide protection from the elements. The fineness of this mixture provides the ability for
some crack penetration.
Type II. This aggregate gradation is used to fill surface voids, address more severe surface
distresses, seal, and provide a durable wearing surface.
Type III. This aggregate gradation provides maximum skid resistance and an improved wearing
surface.
Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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MINERAL FILLER
Mineral filler may be used to improve mixture consistency and to adjust mixture breaking and curing
properties. Portland cement, hydrated lime, limestone dust, fly ash, or other approved filler meeting the
requirements of ASTM D 242 shall be used if required by the mix design.
Typical use levels are normally 0.0 - 3.0 percent and may be considered part of the aggregate gradation.
WATER
The water shall be free of harmful salts and contaminants. If the quality of the water is in question, it
should be submitted to the laboratory with the other raw materials for the mix design.
ADDITIVES
Additives may be used to accelerate or retard the break/set of the slurry seal. Appropriate additives, and
their applicable use range, should be approved by the laboratory as part of the mix design.
LABORATORY EVALUATION
GENERAL
Before work begins, the contractor shall submit a signed mix design covering the specific materials to be
used on the project. This design will be performed by a laboratory which has experience in designing
Polymer-Modified Emulsified Asphalt Slurry Seal. After the mix design has been approved, no material
substitution will be permitted unless approved by the B.A.R.
ISSA can provide a list of laboratories experienced in slurry seal design.
MIX DESIGN
Compatibility of the aggregate, emulsified asphalt, water, mineral filler and other additives shall be
evaluated in the mix design. The mix design shall be completed using materials consistent with those
supplied by the contractor for the project. Recommended tests and values are as follows:
Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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The Wet Track Abrasion Test is performed under laboratory conditions as a component of the mix design
process. The purpose of this test is to determine the minimum asphalt content required in a slurry seal
system. The Wet Track Abrasion Test is not recommended as a field quality control or acceptance test.
ISSA TB 136 describes potential causes for inconsistent results of the Wet Track Abrasion Test.
The mixing test is used to predict the time the material can be mixed before it begins to break. It can be a
good reference check to verify consistent sources of material. The laboratory should verify that mix and
set times are appropriate for the climatic conditions expected during the project.
The laboratory shall also report the quantitative effects of moisture content on the unit weight of the
aggregate (bulking effect) according to AASHTO T19 (ASTM C29). The report must clearly show the
proportions of aggregate, mineral filler (if used) and polymer-modified emulsified asphalt, based on the
dry weight of the aggregate.
The percentages of each individual material required shall be shown in the laboratory report. Based on
field conditions, adjustments within the specific ranges of the mix design may be required.
The component materials shall be designed within the following limits:
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Roadway Surface Treatment Services
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MIX TOLERANCES
Tolerances for the slurry seal mixture are as follows:
a. After the polymer-modified residual asphalt content is determined, any variations (based on percent of
weight of dry aggregate) that will be permitted must be defined in the mix design for the project.
b. The rate of application shall not vary more than ± 2 lb/yd2 (± 1.1 kg/m2) when the surface texture does
not vary significantly.
EQUIPMENT
GENERAL
All equipment, tools, and machines used in the application of slurry seal shall be maintained in
satisfactory working condition at all times.
MIXING EQUIPMENT
The machine shall be specifically designed and manufactured to apply polymer-modified slurry seal. The
material shall be mixed by an automatic-sequenced, self-propelled, slurry seal mixing machine of either
truck-mounted or continuous-run design. Continuous-run machines are those that are equipped to self-
load materials while continuing to apply slurry seal. Either type machine shall be able to accurately
deliver and proportion the mix components through a mixer and to discharge the mixed product on a
continuous-flow basis. Sufficient storage capacity for all mix components is required to maintain an
adequate supply to the proportioning controls.
The B.A.R. should decide which type of equipment best suits the specific project. In some cases, truck-
mounted machines may be more suited, i.e. cul-de-sacs, small narrow roadways, parking lots, etc. On
some projects, continuous-run equipment may be chosen due to the continuity of mix and the reduction of
start-up joints. Generally, truck-mounted machines or continuous-run machines may be used on similar
projects.
If continuous-run equipment is used, the machine shall provide the operator with full control of the
forward and reverse speeds during application of the slurry seal. It shall be equipped with a self-loading
device and opposite-side driver stations. The self-loading device, opposite-side driver stations, and
forward and reverse speed controls shall be of original-equipment-manufacturer design.
PROPORTIONING DEVICES
Individual volume or weight controls for proportioning mix components shall be provided and properly
labeled. These proportioning devices are used in material calibration to determine the material output at
any time.
Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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SPREADING EQUIPMENT
The mixture shall be agitated and spread uniformly in the spreader box by means of twin-shafted paddles
or spiral augers fixed in the box. With polymer-modified, quick-set systems, mechanical agitation may
extend mix time. The slurry seal mixture shall have the proper consistency as it enters the spreader box.
Spraying of additional water into the spreader box will not be permitted.
A front seal shall be utilized to ensure no loss of the mixture at the road contact point. The rear seal shall
act as final strike-off and shall be adjustable. The spreader box and rear seal shall be designed and
operated to provide uniform mix consistency behind the box. The spreader box shall have suitable means
to side shift to compensate for variations in the pavement geometry. A burlap drag or other approved
screed may be attached to the rear of the spreader box to provide a highly textured uniform surface. A
drag stiffened by hardened slurry is ineffective and should be replaced immediately.
AUXILIARY EQUIPMENT
Suitable surface preparation equipment, traffic control equipment, hand tools, and other support and
safety equipment necessary to perform the work shall be provided by the contractor.
CALIBRATION
Each Micro-Surface unit to be used shall be calibrated in the presence of the Project Manager prior to
construction. Previous calibration documentation covering the exact materials to be used may be accepted
provided they were made during the calendar year. No machine shall be allowed to work on the project
until the calibrations have been completed and/or accepted.
VERIFICATION
The test strips will be laid (location to be determined by the Project Manager before construction begins.
The Project Manager will observe the test strip for verification or rejection according to the specifications.
Upon failure of any of the test, additional test strips will be laid at no cost to the City. The square yards of
the first test strip will be measured and paid for at the contract unit price.
(Keeping proper consistency is a major concern. A wet mix will cause an asphalt rich surface. Consistency
can be checked in the field by making a line through the micro-surface immediately behind the spreader
box. If the line stays, the mix is at a proper consistency level. If the line fills up, the mix is too wet.)
LIMITATIONS
WEATHER
All Micro-Surfacing will be applied between (April 1st and July 1st) and (September 1st November 15th)
unless otherwise approved by the Project Manager. This is contingent upon the weather conditions met
the requirements below.
Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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The Micro-Surfacing shall be applied only if the air and pavement temperature is 50° degrees
Fahrenheit and rising.
No Micro-Surfacing shall be applied:
1. In the period following precipitation with water remaining on the surface to be coated.
2. In foggy conditions.
3. If there is a threat of rain before the micro- surfacing can fully cure.
4. If there is danger that the finished product will freeze within 24 hours after application.
5. If weather conditions prolongs opening to traffic beyond the time specified by the Project
Manager.
The micro-surface will be placed on the location and within the time limits as specified by the
Project Manager.
CONDITION AND TYPE PAVEMENT TO BE TREATED
Any base failures, severe surface defects, or similar conditions which are present will be properly repaired
by the city to ensure correct application and performance of the micro-surface. Micro-Surface normally
adheres to asphalt more readily than, concrete, especially worn or polished areas. Heavy traffic areas,
especially those on concrete, require greater care in selection of type of coarseness of micro-surface
allowing the surface to fully cure before opening to traffic, and the placing of either a tack coat or a second
coat of micro-surface for greater adhesion and wear purposes.
NOTIFICATIONS
It shall be the Contractor’s duty to notify all homeowners and businesses affected by the construction a
minimum of 48 hours in advance of the resurfacing. Should the work not occur on the specified day, new
notification will be distributed as required. Suitable no parking signs will be properly posted on streets, 48
hours prior to starting work, where parked vehicles would interfere with the surfacing.
Contractor must adhere to daily schedule. The Project Manager must approve any changes in order
of which street is resurfaced. It is imperative to follow the schedule just in case vehicles have to moved.
Any changes in the daily schedule must communicated to Project Manager.
TRAFFIC CONTROL
It shall be the Contractor’s responsibility to provide adequate traffic control measures, such as barricades,
cones, advance warning signs, flag person, etc. to protect the uncured micro-surface from all types of
traffic and provide traffic safety in the construction area. These measures shall be in accordance with the
most current version of the Texas Manual on Uniform Traffic Control Devices for Streets and Highways.
The Contractor will not be allowed to close a residential street if the street segment is more than 500 feet
in length. The Contractor shall only be allowed apply the micro seal to one half of the street at time. The
contractor will use cones and flaggers to direct traffic around freshly laid micro seal until it has had
sufficient time to cure.
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Roadway Surface Treatment Services
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Opening to traffic does not constitute acceptance of the work. Any damage to the uncured micro-surface
will be the responsibility of the Contractor and will be repaired as directed by the Project Manager.
Approved temporary lane marking will be provided by the Contractor for placement as directed by the
Project Manager.
TEMPORARY MARKINGS AND LANE DELINEATION
Whenever the work causes obliteration of pavement markings or delineation, temporary markings or
delineation shall be in place prior to opening the traveled way to public traffic. Lane line and centerline
pavement delineation shall be provided at all times for traveled ways open to public traffic. Other markings
such as crosswalks, stop bars, and pavement arrows shall be delineated prior to opening the roadway to
public traffic if directed by the Project Manager.
All work necessary to establish satisfactory temporary marking and lane delineation shall be performed by
the Contractor. Surfaces on which temporary marking and lane delineation is to be applied shall be cleaned
of all dirt and loose material, and shall be dry when it is applied. Temporary markings and lane delineation
shall be maintained for a period four weeks.
Temporary lane delineation shall consist of either a 4-inch by 4-inch square stripe or a 4-inch reflectorized
tab, as directed by the Project Manager. Temporary lane delineators shall be placed on lane lines and
centerlines at longitudinal intervals of not more than 24 feet apart, or 12 feet apart on radii. The temporary
markings and lane delineators shall be the same color as the lane line, centerline, or pavement marking
being replaced.
Temporary markings and lane delineation shall not be paid for as a separate pay item and shall be considered
subsidiary to the contract unit price per square yard of Slurry Seal or Micro Surfacing, which pay item shall
be the total compensation for the furnishing of all labor, materials, tools, equipment, and incidentals
necessary to locate, install, and maintain the temporary markings and lane delineation.
STORAGE AND STOCKPIING
STOCKPILING OF AGGREGATE
Precautions shall be taken to ensure the aggregate does not become contaminated with over-sized rock,
clay, silt or excessive amounts of moisture. The stockpile shall be kept in areas that have good drainage.
Segregation of aggregates proposed for use and as supplied to the mixing plant shall be uniform.
STORAGE SITE
If desired, the Contractor shall provide a suitable storage facility for all equipment and materials needed to
perform the work. This site should be located as close as possible to the area of work being done to reduce
turnaround time and ensure an acceptable rate of work. Any site selected shall be subjected to final approval
by the Project Manager. Erosion control measures shall be implemented as needed to comply with the law
and City of Denton ordinances.
Scope of Work/Technical Specifications
Polymer-Modified Emulsified Asphalt Slurry Seal
Roadway Surface Treatment Services
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SURFACE PREPARATION
1. The area to be sealed shall be thoroughly cleaned of all vegetation, loose aggregate, and soil.
2. Water used shall be applied at a rate to dampen the entire surface without any free-flowing water
ahead of the spreader box.
3. Any ruts in excess of 1/2" shall be filled using a rut box prior to final surface treatment.
4. All manholes and water valves will be covered with plastic prior to Micro-Surfacing.
5. The Contractor shall remove all raised pavement markers in a manner which will protect and ensure
no damage to the existing pavement. Any pavement damaged by the Contractor's operations shall be
repaired at no cost to the City. Any excess debris shall be removed by the Contractor at no cost to
the City.
6. All crosswalk bars/arrows/stop bars shall be removed from the existing pavement prior to
Micro-Surfacing.
7. Any thermoplastic and/or any striping that exceeds 1/8 of an inch: Thickness shall be removed
from the existing pavement prior to Micro-Surfacing.
8. All other striping shall be covered with a tack coat prior to Micro-Surfacing.
9. All exposed concrete pavement shall be covered with a tack coat prior to
TACK COAT
If required, the Contractor shall apply a tack coat or a second coverage of Micro-surface on brick, concrete,
or other highly absorbent or polished pavements. If a tack coat is required, a 1-part emulsion, 3-part water
tack coat of the same asphalt emulsion type and grade as specified for the Micro-surface is required.
Rate of application: 0.05 to 0.10 gallons per square yard. All debris and unused material shall be removed.
APPLICATION
GENERAL
If required, it is recommended that a test strip be placed in conditions like those expected to be encountered
during the project.
The surface may be wet with water ahead of the spreader box. The rate of application of the water spray
shall be adjusted during the day to suit temperature, surface texture, humidity, and dryness of the pavement.
Pooling or standing water shall be avoided.
The slurry seal shall be of the desired consistency upon exiting the mixer. Enough material shall be always
carried in all parts of the spreader box so that complete coverage is achieved. Overloading of the spreader
shall be avoided.
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Roadway Surface Treatment Services
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No lumping, balling, or unmixed aggregate shall be permitted.
Significant streaks, such as those caused by oversized aggregate or broken mix, shall not be left in the
finished surface. If excessive streak occurs, the job will be stopped until the cause of the problem has been
corrected. Some situations may require screening the aggregate prior to loading it into the units going from
the stockpile area to the jobsite.
RATE OF APPLICATION
The slurry seal mixture shall always be of proper consistency to provide the application rate required by
the surface condition. The average application rate shall be in accordance with the following table:
Suggested application rates are based upon the weight of dry aggregate in the mixture. Application rates
are affected by the unit weight and gradation of the aggregate and the demand of the surface to which the
slurry seal is being applied.
JOINTS
No excessive buildup or uncovered areas, or unsightly appearance shall be permitted on longitudinal or
transverse joint. An excessive overlap will not be permitted on longitudinal joints. The Contractor shall
provide suitable width spreading equipment to produce a minimum number of longitudinal joints
throughout the project. Longitudinal joints shall be placed on lane lines when possible. If half passes are
used they shall not be the last pass of any paved area. A maximum of 3.0” inches shall be allowed for
overlap. Also, the joint shall have no more than a 0.25” inches difference in elevation when measured
by placing a 10 ft. straight edge over the joint and measuring the elevation difference.
MIXTURE
The slurry seal shall possess sufficient stability so that premature breaking of the material in the
spreader box does not occur. The mixture shall be homogeneous during and following mixing and
spreading. It shall be free of excess liquids which create segregation of the aggregate. Spraying
additional water into the spreader box will not be permitted.
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Roadway Surface Treatment Services
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HAND WORK
In areas where the spreader box cannot be used, the micro shall be applied by hand squeegees to provide
complete and uniform coverage. Any joint or cracks not dilled by the micro shall be corrected by use of
hand squeegees. Hand work shall be completed during the machine applying process. Due to difficulty in
hand working micro-surfacing material due to the quickset nature of the emulsion, hand work areas should
be kept to a minimum.
LINES
Straight lines along curb gutters and shoulder will be required. No runoff on these areas will be permitted.
Lines at intersections shall be kept straight to provide a good appearance. Micro shall be placed at the lip
of the gutter or at a distance from the face of the curb as directed by the Project Manager.
ROLLING
If required, specified areas shall be rolled by a self-propelled 10 tons pneumatic roller with tire pressure of
50 PSI and equipped with a water spray system. The micro-surfaced pavement shall be subjected to a
minimum of 2 full coverages by the roller. Rolling should not commence until the micro until the micro
has cured enough so that it will not pick up on the tires. (Rolling is normally not required). In areas of high
traffic volume and subject to slow turning, e.g. major intersections, rolling may be feasible.
CURING
All traffic shall be kept off the micro until it has cured to a firm condition that will prevent damage to the
micro. The emulsified asphalt shall be so formulated that when the paving mixture is applied with the
relative humidity at no more than 50% and ambient air temperature of at least 50 degrees
Fahrenheit, it will cure sufficiently such that uniformly moving traffic can be allowed on completed
travel lanes within 1 hour after placement with no damage to the surface. Failure to comply with this
requirement may result in cessation of all work until such time that the Contractor provides the proper
adjustments in his operations. If determined necessary by the Project Manager, the mixture properties shall
be adjusted according to humidity conditions and ambient air temperatures to allow uniformly moving
traffic on completed travel lanes within 1 hour after placement with no damage to the surface.
Failure to comply with this requirement may result in cessation of all work until such time that the
Contractor provides the proper adjustments in his operations. Protect other locations subject to sharp
turning or stopping and starting traffic for longer periods when necessary. Any uncured micro damaged
will be repaired to the satisfaction of the Project Manager at the Contractor’s expense.
CLEAN-UP
All objects covered (manhole covers, valve covers, grate inlets, etc) shall be restored to their original
integrity. The Contractor shall remove all unused material and debris from the site prior to final acceptance.
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QUALITY CONTROL
INSPECTION
Inspectors assigned to projects must be familiar with the materials, equipment and application of slurry
seal. Local conditions and specific project requirements should be considered when determining the
parameters of field inspection.
Proper mix consistency should be one of the major areas of inspector’s concern. If mixes are too dry,
streaking, lumping and roughness will be present in the mat surface. Mixes applied too wet will flow
excessively and not hold straight lane lines. Excessive liquids may also cause an asphalt-rich surface with
segregation.
MATERIALS
To account for aggregate bulking, it is the responsibility of the contractor to check stockpile moisture
content and to set the machine accordingly. At the B.A.R.’s discretion, material tests may be run on
representative samples of the aggregate and emulsion. Tests will be run at the expense of the buyer. The
buyer must notify the contractor immediately if any test fails to meet the specifications.
SLURRY SEAL
If required, representative samples of the slurry seal may be taken directly from the slurry unit(s).
Consistency (ISSA TB No. 106) and residual asphalt content (ASTM D2172) tests may be run on the
samples. Please note that the consistency test may not be applicable to certain Quick-Set and Quick-Traffic
systems because of erratic results due to setting characteristics. If this test is run, it must be performed
immediately after the sample is taken. Tests will be run at the expense of the buyer. The buyer must notify
the contractor immediately if any test fails to meet specifications.
Data obtained from the proportioning devices on the slurry seal unit may be used to determine individual
material quantities and application rate.
NON-COMPLIANCE
If any two successive tests fail on the stockpile aggregate, the job shall be stopped. If any two successive
tests on the mix from the same machine fail, the use of the machine shall be suspended. It will be the
responsibility of the contractor, at his expense, to prove to the B.A.R. that the problems have been corrected.
BASIS OF PAYMENT
The authorized and accepted quantity of polymer modified micro-surfacing treatment shall be paid for at
the contract unit price bid per square yard accepted by the City, completed in place in accordance with
these specifications. The Bidder may submit separate bid price per square yard for preventive
maintenance work and maintenance of utility cut surface. The unit price bid shall be considered full
compensation for all aggregate, polymer modified asphalt emulsion (including mineral filler, water,
modifiers and additives), emulsion for tack coat, material, labor, tools, equipment, cleaning the existing
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Roadway Surface Treatment Services
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pavement, maintenance of traffic and all other incidentals necessary to complete the work in accordance
with these specifications and the bid documents. Payment shall be restricted to only those micro surface
areas in which the specified range of dry weight aggregate is 22 to 28 lbs. per square yard. No payment
shall be made for micro-surfacing treatment not authorized or approved by the Project Manager.
SURFACE TREATMENT INSPECTION PROCEDURES
1. All locations will be selected and subject to final approval by the Project Manager. Non-
compliance will result in nonpayment.
2. No work will commence on any location until approval by the Project Manager. Non-compliance
will result in nonpayment.
3. All pavement cleaning (sweeping, vegetation removal, etc.), and covering of appurtenances to be
performed by the contractor as directed in the Micro-Resurfacing Specification will be subject to
the final approval and acceptance of the Project Manager. Non-compliance will result in
nonpayment.
4. All locations will be subjected to final approval in regards to appearance by the Project Manager.
Any work directed by the Project Manager to correct any appearance defect will be subject to the
final approval of the Project Manager. Non-compliance will result in nonpayment.
5. No location will be open to traffic without the approval of the Project Manager. Any locations
damaged due to non-compliance will be repaired as directed by the Project Manager at the
Contractor’s expense.
CONSTRUCTION METHODS:
1. General: It shall be the responsibility of the Contractor to produce, transport, and place the
specified paving mixture in accordance with those specifications and as approved by the
Engineer.
2. Surface Preparation:
(a) The area to be sealed shall be thoroughly cleaned of all vegetation, loose aggregate, and
soil.
(b) Water used shall be applied at a rate to dampen the entire surface without any free
flowing water ahead of the spreader box.
(c) Any ruts in excess of 1/2" shall be filled using a rut box prior to placing final surface
treatment.
(d) All manholes and water valves will be covered with plastic prior to placing micro-surfacing.
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(e) The Contractor shall remove all raised pavement markers in a manner which will protect
and ensure no damage to the existing pavement. Any pavement damaged by the
Contractor's operations shall be repaired at no cost to the City. Any excess debris shall be
removed by the Contractor at no cost to the City.
(f) All crosswalk bars or other fabricated markings shall be removed from the existing
pavement prior to placing micro-surfacing.
3. Spreading Equipment: The paving mixture shall be spread uniformly by means of a mechanical
type squeegee box attached to the mixer, equipped with paddles to agitate and spread the materials
throughout the box. A front seal shall be provided to ensure no loss of the mixture at the road
contact surface. The rear seal shall act as a final strike-off and shall be adjustable. The mixture
shall be spread to fill cracks and minor surface irregularities and leave a uniform skid resistant
application of aggregate and asphalt on the surface.
The spreader box and rear strike-off shall be so designed and operated that a uniform consistency
is achieved to produce a free flow of material to the rear strike-off. The seam where two spreads
join shall be neat appearing and uniform.
4. Notification: It shall be the responsibility of the Contractor to notify all residents adjacent to the
project of micro-surfacing operation and schedules. Such notices shall be given at least 48 hours
before the work begins. If this requirement is not met then the Contractor to move on to the
next street that does meet the requirement.
WARRANTY SERVICE CLAUSE: Under the terms of the warranties which arise from these Contract documents and/or by the terms of any applicable special warranties required by the Contract documents, if any of the work in accordance with this Contract is found to not be in accordance with the requirements of the Contract documents, the Contractor shall correct such work promptly after receipt of written notice from the City of Denton or the architect, Project, or other entity as the Contract documents may provide. This obligation shall survive acceptance of the work under the Contract and termination of the Contract. In order to facilitate a prompt response, Contractor agrees to provide for warranty service to the extent practical from local businesses, including goods and services, when such goods and services are comparable in availability, quality and price. If Contractor fails within a reasonable time after written notice to correct defective work or to remove and replace rejected work, or if Contractor fails to perform the work in accordance with the Contract documents, or if Contractor fails to comply with any provision in the Contract documents, either the City of Denton its designee may, after seven (7) days written notice to Contractor, correct and remedy any such deficiency at the expense of the Contractor.
Warranty Performance Criteria: Surface deficiencies of the Micro-Surfacing that will be measured
during the warranty shall not exceed the following threshold values. The threshold values for each
parameter will be determined separately. If any threshold value is exceeded during the warranty period the
Micro-Surfacing will be considered in non-compliance with the warranty performance provision.
The Contractor shall make repairs to all defects at no cost to the City of Denton
Flushing/Skid Loss: No more than 5 percent of the area in a segment where the skid number is less than
40.
Delamination: No more than 2 percent of the area in a segment.
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Weathering and Raveling: No more than 5 percent of the area in a segment.
Rutting: Rut depths shall not exceed ¼-inch in the entire segment during the first 120 calendar days
after the acceptance date of construction. Rut depths at the end of the warranty period shall not exceed
3/8-inch. Pavement segments where the rut depth exceeds 1-inch are excluded from the warranty for
rutting threshold level.
Other: Not to exclude any other surface deficiencies that the inspector may find.
Corrective work is limited to those segments that exceed the specified threshold values and shall be
performed before conclusion of the warranty period of one year or within such other time frame as agreed
to by the Department and the Contractor.
DEFINITIONS:
A. Paving Pass: The section of pavement consisting of a typical lane width delineated by the edge of
the shoulder, lane line or centerline.
B. Rut Depth: The greatest perpendicular distance measured from the pavement surface to the bottom
of a 10-foot straight edge.
C. Segment: A portion of roadway, one paving pass wide and 500 feet in length.
Surface deficiencies caused by deficiencies in the underlying pavement or base course layers are not subject
to this warranty. The warranty applies solely to the Micro-Surfacing placed under this contract.
Surface deficiencies that will be evaluated in the Micro-Surfacing warranty performance criteria are defined
as follows:
D. Flushing/Skid Loss: Excess asphalt binder that occurs on the Micro-Surfacing that creates a shiny,
reflective condition that becomes tacky to the touch at higher temperatures, and/or results in skid
numbers less than 40.
E. Delamination: A physical separation of the Micro-Surfacing from the underlying pavement surface.
F. Raveling: Wearing away of the Micro-Surfacing, from the underlying pavement surface course,
G. Rutting: The consolidation, pushing or shoving of the Micro-Surfacing due to traffic loading.
H. Other: Any other surface deficiencies not listed above.
ACCESS TO PRIVATE PROPERTIES: The Contractor shall put all private drives in an accessible condition to
allow residents ingress and egress before leaving the job site for an extended period of time, except during the pouring
and curing of drive approaches. "Extended period of time" is defined as overnight, weekends, holidays, or periods of
inclement weather. The Contractor will leave with the Project Manager the phone numbers of responsible persons
available twenty-four (24) hours a day to handle emergencies concerning egress and ingress. If a vehicle becomes
stranded due to an inaccessible condition, any legitimate claims arising from such conditions shall be the sole
responsibility of the Contractor. If such claims are not settled prior to the monthly pay estimate, they shall be deducted
from the estimate.
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USE OF PRIVATE PROPERTY: The Contractor shall not at any time use private property to park or turn around
construction vehicles or store equipment and/or materials without the written permission of the property owner
involved. The Contractor shall not at any time use water metered by meters set for the property owner's use without
permission of the property owner(s).
PROTECTION OF THE PUBLIC: The Contractor shall at all times conduct the work in such manner as to
ensure the least possible obstruction to public traffic and protect the safety of the public. Public safety and
convenience and provisions therefore made necessary by the work, shall be the direct responsibility of the
Contractor and shall be performed at his entire expense.
Materials placed on the site or materials excavated and the construction materials or equipment used shall be located
to cause as little obstruction to the public as possible.
The Owner reserves the right to remedy any neglect on the part of the Contractor regarding public convenience and
safety, which may come to its attention. The cost of such work done or materials furnished by the Owner shall be
deducted from monies due or to become due to the Contractor.
PROTECTION OF ADJACENT PROPERTY: The Contractor shall be responsible for the protection of all fences,
trees, curb and gutter, and other improvements on the property adjoining the construction sites from damage by the
Contractor's equipment and men. The Contractor shall be responsible for notifying the property owners in advance of
any trimming to be done on trees. The Contractor will notify the City of any trees, shrubs, or bushes that must be
removed by the construction. No trees will be removed by the Contractor until permission is granted by the Project
Manager his designated representative. The Contractor will not be allowed to place excess material, forms, equipment,
or any other material outside the street right-of-way without written permission of the property owner and approval
of the Project Manager.
EVALUATION CRITERIA:
Core Evaluation Criteria for Roadway Surface Treatment Services
1. Technical Approach & Methodology- 25%
Provide a detailed summary the Offeror shall demonstrate means and methods of the following:
• Clarity and feasibility of proposed surface treatment methods (e.g., chip seals, slurry seals, micro-
surfacing)
• Alignment with pavement condition and lifecycle goals
• Innovation in materials or techniques
• Environmental considerations and sustainability
2. Experience & Qualifications- 25%
Submit details of five (5) similar projects completed within the last ten (10) years. The Offeror should include
details for each project submitted, along with the following:
• Proven track record with similar roadway projects
• Certifications, licenses, and compliance with DOT standards
• References from previous clients or municipalities
• Staff expertise and training
3. Cost Proposal- 35%
• Total project cost and cost per square yard/mile
• Breakdown of labor, materials, equipment, and contingencies
• Life-cycle cost analysis (LCCA) to assess long-term value
4. Schedule & Project Management- 15%
Submit a summary of your team’s approach in providing successful roadway treatment surfaces, including the
following:
• Realistic timeline for completion
• Phasing and traffic management plans
• Resource allocation and contingency planning