USACE / NAVFAC / AFCESA / NASA UFGS-32 01 13 (August 2008)
---------------------------
Preparing Activity: USACE Superseding
UFGS-32 01 13 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 32 01 13
BITUMINOUS SEAL AND FOG COATS
08/08
NOTE: This guide specification covers the requirements for bituminous surface
coatings for low volume roads, parking areas, and other general applications.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
PART 1 GENERAL
NOTE: Bituminous seal coat should not be used on primary roads or airfield
areas. Fog seals lower the frictional resistance of paved surfaces and will
not be used on runways, high speed taxiway turnoffs, or moderate to high speed
roads unless approval is obtained from NAVFACENGCOMHQ, AFCESA or the TSMCX.
This section must be edited to remove all references to Fog Seal when it is
not required in the project.
UFC 3-250-03 should be used for guidance in preparing these specifications.
1.1 MEASUREMENT AND PAYMENT PROCEDURES
NOTE: Delete this paragraph when lump sum bidding is used.
Measure the quantities of bituminous material and aggregate used in the accepted work and to be paid for, provided
that the measured quantities are not more than 10 percent over the specified application rate. Any amount of
bituminous material and aggregate more than 10 percent over the specified application rate for each application
will be deducted from the measured quantities except for irregular areas where hand spraying of the bituminous
material and hand spreading of the aggregate is necessary.
1.1.1 Bituminous Material Measurement Methods
NOTE: When the bituminous material is measured in liters (gallons), the appropriate
ASTM method will be retained for the type of bituminous material specified.
The amount of bituminous material to be paid for will be measured in [metric 2000 pound tons,] [L at 15.6 degrees
C gallons at 60 degrees F]. Correct volumes measured at temperatures other than 15.6 degrees C 60 degrees F
in accordance with [ASTM D 633] [ASTM D 1250] [, using a coefficient of expansion of 0.00045 per degree C 0.00025
per degree F for asphalt emulsion].
1.1.2 Aggregate Measurement Methods
The amount of aggregate to be paid for will be measured in [metric tons tons] [cubic meters yards] of dry aggregate.
Measurement of the materials shall be by [approved weigh scales] [determining the volume capacity of each vehicle
delivering the material to the site of the work or stockpiles].
1.1.3 Payment
NOTE: Delete this paragraph when lump sum bidding is used.
The quantities of aggregate and bituminous material, determined as specified above, will be paid for at the respective
contract unit prices. Payment will constitute full compensation for all operations necessary to complete the
work as specified herein.
1.1.4 Waybills and Delivery Tickets
NOTE: Delete this paragraph when lump sum bidding is used.
Do not remove bituminous material from the tank car or storage tank until measurements of the remaining quantity
have been taken.
1.2 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS (AASHTO)AASHTO M 20(1970; R 2004) Penetration-Graded Asphalt CementAASHTO M 226(1980; R 2004) Viscosity Graded Asphalt CementAASHTO M 81(1992; R 2004) Cut-Back Asphalt (Rapid-Curing Type)AASHTO M 82(1975; R 2004) Cut-Back Asphalt (Medium-Curing Type)AASHTO T 40(2002; R 2006) Sampling Bituminous Materials][ASTM INTERNATIONAL (ASTM)ASTM C 131(2006)Standard Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles MachineASTM C 136(2006) Standard Test Method for Sieve Analysis of Fine and Coarse AggregatesASTM C 142(1997; R 2004) Standard Test Method for Clay Lumps and Friable Particles in AggregatesASTM C 29/C 29M(2007) Standard Test Method for Bulk Density ("Unit Weight") and Voids in AggregateASTM D 1250(2007) Standard Guide for Use of the Petroleum Measurement TablesASTM D 140(2001; R 2007) Sampling Bituminous MaterialsASTM D 2027(1997; R 2004) Cutback Asphalt (Medium-Curing Type)ASTM D 2028(1997; R 2004) Cutback Asphalt (Rapid-Curing Type)ASTM D 2397(2005) Standard Specification for Cationic Emulsified AsphaltASTM D 2995(1999; R 2004) Determining Application Rate of Bituminous DistributorsASTM D 3381(2005) Viscosity-Graded Asphalt Cement for Use in Pavement ConstructionASTM D 3625(1996; R 2005) Standard Practice for Effect of Water on Bituminous-Coated Aggregate Using Boiling WaterASTM D 4791(2005e1) Flat Particles, Elongated Particles, or Flat and Elongated Particles in Coarse AggregateASTM D 490(1992; R 2005) Road TarASTM D 633(1997; R 2005) Volume Correction Table for Road TarASTM D 75(2003) Standard Practice for Sampling AggregatesASTM D 946(1982; R 2005) Penetration-Graded Asphalt Cement for Use in Pavement ConstructionASTM D 977(2005) Emulsified Asphalt][U.S. FEDERAL HIGHWAY ADMINISTRATION (FHWA)MUTCD(2000) Manual of Uniform Traffic Control Devices]1.3 SYSTEM DESCRIPTION
NOTE: Retain equipment units required for the project and delete all others.
1.3.1 Equipment, Plant and Tools
Equipment, plant and tools used in the work are subject to approval and shall be maintained in a satisfactory
working condition at all times. Provide equipment which is adequate and has the capability of producing the
results specified. Provide calibrated equipment, such as asphalt distributors, scales, batching equipment, spreaders
and similar equipment, that has been recalibrated by an approved calibration laboratory within [12] [_____] months
prior to commencing work [and every [_____] months thereafter, by such laboratory from the date of recalibration,
during the term of the contract]. Submit an equipment list with calibration reports.
1.3.2 Bituminous Distributors
NOTE: The bracketed statements at the end of this paragraph apply specifically
to Fog Seal.
Provide distributors that have pneumatic tires of sufficient size and number to prevent rutting, shoving, or
otherwise damaging any part of the pavement structure. Design and equip the distributor to distribute the bituminous
material in a uniform double or triple lap at the specified temperature, at readily determined and controlled
rates from 0.23 to 9.05 L/square meter 0.05 to 2.0 gallons/square yard, with a pressure range of 172.4 to 517.1
kPa 25 to 75 psi with an allowable variation from the specified rate of not more than plus or minus 5 percent,
and at variable widths. Include in the distributor equipment a separate power unit for the bitumen pump, full-circulation
spray bars, tachometer, pressure gauges, volume-measuring devices, adequate heaters for heating of materials
to the proper application temperature, a thermometer for reading the temperature of tank contents, and a hand-held
hose attachment suitable for applying bituminous material manually to areas inaccessible to the distributor.
Equip the distributor to circulate and agitate the bituminous material during the heating process.[ Provide
distributor with an adjustable, both horizontally and verically, spray nozzle bar. Make normal width of bar
application at least 3.7 m 12 feet, with provisions for lesser or larger width when necessary. Equip distributor
with a meter having a dial registering meters of travel/sec feet of travel/min. Make both dials visible to the
distributor driver. Provide a thermometer and well, not in contact with any heating tubes, for accurately indicating
temperature of asphalt emulsion.]
1.3.3 Aggregate Spreader
The aggregate-spreading equipment shall be adjustable and capable of uniformly spreading aggregate at the specified
rate in a single-pass operation over the surface to be sealed.
1.3.4 Pneumatic-Tired Roller
Provide a pneumatic-tired roller of sufficient size to seat the cover aggregate into the bituminous material
without fracturing the aggregate particles. The rollers shall have a total compacting width of not less than
1.52 m 5 feet. The gross weight shall be adjustable within 3, 572 to 6, 250 kg/m 200 to 350 psi of compacting
width.
1.3.5 Power Brooms and Power Blowers
Provide power brooms and power blowers suitable for cleaning surfaces to [be treated] [which the seal coat is
to be applied].
1.3.6 Scales
NOTE: Delete this paragraph when lump sum bidding is used.
Use scales of sufficient size and capacity to accommodate all trucks hauling aggregates in the job. All scales
shall be tested and approved by an inspector of the state inspection bureau charged with scales inspection within
the State in which the project is located. If an official of the inspection bureau is not available, test the
scales in accordance with the State specifications in the presence of the Contracting Officer. Keep the necessary
number of standard weights on hand at all times for testing the scales.
1.3.7 Weighhouse
NOTE: Delete this paragraph when lump sum bidding is used.
Provide a weatherproof weighhouse, constructed in a manner that will afford adequate protection for the recording
devices on the scales, of a suitable size with one sliding window facing the scales platform, one end window,
and a desk-type area at least 600 mm 2 feet wide by 1.8 m 6 feet long.
1.3.8 Storage Tanks
Provide tanks capable of heating the bituminous material, under effective and positive control at all times,
to the required temperature. Accomplish heating by steam coils, hot oil, or electricity. Affix to the tank
an armored thermometer with a range from 37.8 to 148.9 degrees C 100 to 300 degrees F so that the temperature
of the bituminous material may be read at all times.
1.3.9 Power Rollers
Provide self-propelled tandem and three-wheel type rollers, weighing not less than 4.54 metric tons 5 tons and
suitable for rolling bituminous pavements. The wheels of the rollers shall be equipped with adjustable scrapers.
Equip the rollers with water tanks and sprinkling apparatus for keeping the wheels wet in order to prevent adherence
of the bituminous material to the wheels.
1.3.10 Single-Pass, Surface-Treatment Machines
Provide machines capable of spraying bituminous material and spreading aggregate in one pass; of distributing
the bituminous material uniformly, at even heat, and in controlled amounts; and inmediately spreading aggregates
uniformly, in controlled amounts, over the surface to be sealed.
1.3.11 Vacuum Sweepers for Fog Seal
Provide self-propelled, vacuum pickup sweeper capable of removing loose sand, water, and debris from pavement
surface.
1.4 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are for [Contractor Quality Control approval.][information only. When used, a designation following the "G"
designation identifies the office that will review the submittal for the Government.] Submit the following in
accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-03 Product Data
Waybills and Delivery Tickets
Waybills and delivery tickets, during the progress of the work. Before the final statement
is allowed, file certified waybills and delivery tickets for all materials used in the work
covered by this section.
Equipment List
List of equipment used in the project along with calibration reports.
Inspection Reports
Reports of climatic temperature during application of fog seal, emulsion temperature and rate.
SD-04 Samples
Bituminous Materials
Aggregates
From each source of supply, a 4 L one gallon sample of bituminous material and a 23 kg 50
pound sample of aggregate for each aggregate size.
Fog Seal[; G][; G, [_____]]
Submit in accordance with paragraph titled "Sample Application", for approval and selection
of one of the trial application rates.
SD-06 Test Reports
Tests
Copies of the test results, within 24 hours of the completion of the test. Certified copies
of the aggregate test results, not less than [30] [_____] days before the material is required
in the work. Certified copies of the bituminous materials test reports indicating compliance
with applicable specified requirements, not less than [30] [_____] days before the material
is required in the work. A copy of the calibration test results, before the bituminous distributor
and aggregate spreader are used on the job.
1.5 QUALITY ASSURANCE
NOTE: Keep applicable tests and delete the others depending on whether this
Section is used for Seal or Fog Coat.
Perform sampling and testing using an approved commercial testing laboratory or facilities furnished by the Contractor.
No work requiring testing will be permitted until the facilities have been inspected and approved. The first
inspection will be at the expense of the Government. Costs incurred for any subsequent inspection will be charged
to the Contractor. Perform tests in sufficient numbers, and at the location and times directed, to ensure that
the materials meet specified requirements.
1.5.1 Samples
Take aggregate samples for laboratory tests in accordance with ASTM D 75. Take samples of bituminous material
in accordance with AASHTO T 40 or ASTM D 140.
1.5.2 Aggregates Source
Select sources from which aggregates are to be obtained and notify the Contracting Officer within 15 days after
the award of the Contract. Perform tests for the evaluation of aggregates by using an approved commercial laboratory
at no expense to the Government. Tests for determining the suitability of aggregate shall include, but not limited
to: gradation in accordance with ASTM C 136, abrasion resistance in accordance with ASTM C 131, clay lumps and
friable particles in accordance with ASTM C 142, unit weight and voids in accordance with ASTM C 29/C 29M, and
flat and elongated particles in accordance with ASTM D 4791. The use of an antistripping agent is subject to
approval by the Contracting Officer.
1.5.3 Bituminous Material Source
Select sources from which bituminous materials are to be obtained and notify the Contracting Officer within 15
days after the award of the contract.
1.5.4 Equipment Calibration
NOTE: Bracketed statements apply to Fog Seal; remove when Fog Seal is not requirede
in the project.
Furnish all equipment, materials and labor necessary to calibrate the bituminous distributor and the aggregate
spreader. Perform all calibrations with the approved job materials and prior to applying the specified coatings
to the prepared surface. Perform calibration of the bituminous distributor in accordance with ASTM D 2995.[
Inspect all equipment prior to application of fog seal. Perform work to calibrate tank and measuring devices
of the distributor. Perform inspection and calibration at the beginning of the work and at least once a day
during construction.]
1.6 DELIVERY, STORAGE, AND HANDLING
Deliver emulsified asphalt (fog seal) to the site in a homogenous and undamaged condition. Inspect the materials
for contamination and damage. Unload and store the materials with a minimum of handling. Protect stored aggregate
from contamination and segregation. Replace defective or damaged materials.
1.7 ENVIRONMENTAL REQUIREMENTS
NOTE: Retain correct temperatures depending on the type of coating used for
the project.
Apply the coating when the existing surface is dry, and when the weather is not foggy, rainy, or when the wind
velocity will prevent the uniform application of the bitumen [or aggregates]. [Apply the bituminous seal coat
only when the atmospheric temperature is above 15.5 degrees C 60 degrees F in the shade and when the pavement
surface temperature is above 15.5 degrees C 60 degrees F, unless otherwise directed.] [Apply fog seal when atmospheric
temperature is above 10 degrees C 50 degrees F and rising or when pavement temperature is above 15.5 degrees
C 60 degrees F, unless otherwise directed.]
PART 2 PRODUCTS
2.1 BITUMINOUS MATERIAL FOR SEAL COAT
NOTE: One type of bituminous material will be retained. All other materials
and references will be deleted.
Cutback asphalt grades MC- or RC-800, and MC- or RC-250, in order of preference,
are recommended for most normal seal coat applications where a rapid-setting
binder providing maximum "hold" of cover aggregate is desired. Where cooler
temperatures are anticipated, preference should be given to the use of MC- or
RC-3000 in very warm climates when work will be performed during periods of
high ambient temperature.
Emulsified asphalt grades RS-1, RS-2, CRS-1, and CRS-2 are suitable for seal
coat applications. Emulsions are better suited to coat aggregate when the aggregate
moisture content is over 1 percent but less than 3 percent. The following considerations
should be included in the evaluation of alternate grades to be specified for
the project:
a. Local practice and experience, as well as availability and cost of various
grades within the area.
b. The rapid-setting emulsions, particularly the cationic types, are effective
when damp aggregates must be used.
c. Where cooler temperatures are anticipated, consider the use of CRS-1 and
CRS-2 grades.
d. Anionic emulsions provide better adhesion to basic aggregates such as limestone,
while cationic emulsions are better with acidic aggregates such as silicates.
Asphalt cement penetration grades 120-150 and 200-300, in order of preference,
are suitable for most normal seal coat applications. Where cooler temperatures
are anticipated, preference should be given to the use of 200-300 grade.
Tar grades RT-9 and RT-8 are suitable for most normal seal coat applications.
Where cooler temperatures are anticipated, consider the use of grades RT-6 and
RT-7. Consider the use of grades RT-10 and RT-11 in very warm climates when
work will be performed during periods of high ambient temperature.
Bituminous material shall conform to [AASHTO M 20] [AASHTO M 81] [AASHTO M 82] [AASHTO M 226] or [ASTM D 490]
[ASTM D 946] [ASTM D 977] [ASTM D 2027] [ASTM D 2028] [ASTM D 2397] [ASTM D 3381], [grade [_____]] [penetration
grade [_____]].
2.2 AGGREGATE FOR SEAL COAT
NOTE: The aggregate gradation to be used will be retained in Table I and the
remaining gradations deleted.
Provide aggregate consisting of crushed stone, crushed gravel, crushed slag, sand and screenings. The moisture
content of the aggregate shall be [not greater than [1] [3] percent] [such that the aggregate will readily bond
with the bituminous material]. Drying may be required, as directed. The aggregate shall conform to the gradation
shown in TABLE I. The aggregate gradation shall be allowed the tolerances given in TABLE II.
TABLE I. AGGREGATE GRADATIONS
(Percent by Weight Passing Square-Mesh Sieves)
Gradation Gradation Gradation
Sieve Size No. 1 No. 2 No. 3
__________ __________ __________ _________
12.5 mm 100 -- --
9.5 mm 85-100 100 --
4.75 mm 10-30 85-100 100
2.36 mm 0-10 10-40 10-40
1.18 mm 0-5 0-10 0-10
0.30 mm -- 0-5 0-5
TABLE I. AGGREGATE GRADATIONS
(Percent by Weight Passing Square-Mesh Sieves)
Gradation Gradation Gradation
Sieve Size No. 1 No. 2 No. 3
__________ __________ __________ _________
1/2 in. 100 -- --
3/8 in. 85-100 100 --
No. 4 10-30 85-100 100
No. 8 0-10 10-40 10-40
No. 16 0-5 0-10 0-10
No. 50 -- 0-5 0-5
TABLE II. AGGREGATE GRADATION TOLERANCES
Material Tolerances
__________ ____________
Aggregate passing the 9.5-mm sieve Plus or minus
and larger sieves 5 percent
Aggregate passing the 4.75 -mm and Plus or minus
smaller sieves 3 percent
TABLE II. AGGREGATE GRADATION TOLERANCES
Material Tolerances
__________ ____________
Aggregate passing the 3/8-in. sieve Plus or minus
and larger sieves 5 percent
Aggregate passing the No. 4 and Plus or minus
smaller sieves 3 percent
2.2.1 Coarse Aggregate
Coarse aggregate shall consist of clean, sound, durable particles meeting the following requirements.
2.2.1.1 Film Retention
The aggregate shall exhibit not less than 95 percent retention of bituminous film.
2.2.1.2 Particle Shapes
The quantity of flat and elongated particles on any sieve shall not exceed 20 percent by weight when determined
in accordance with ASTM D 4791. A flat particle is one having a ratio of width to thickness greater than 3;
an elongated particle is one having a ratio of length to width greater than 3.
2.2.1.3 Weight Loss
The percent weight loss shall not exceed 40 after 500 revolutions, as determined in accordance with ASTM C 131
.
2.2.1.4 Friable Particles
The amount of friable particles shall not exceed 0.1 percent of the total weight of aggregate sample when tested
in accordance with ASTM C 142.
2.2.1.5 Crushed Slag
The dry weight of crushed slag shall not be less than 1200 kg/cubic meter 75 pcf, as determined in accordance
with ASTM C 29/C 29M.
2.2.1.6 Crushed Aggregate
Crushed aggregate retained on the 4.75 mm No. 4 sieve and each coarser sieve shall contain at least 75 percent
by weight of crushed pieces having one or more fractured faces with the area of each face equal to at least 75
percent of the smaller midsectional area of the aggregate particle. When two fractures are contiguous, the angle
between the planes of fractures shall be at least 30 degrees to count as two fractured faces.
2.2.2 Fine Aggregate
Fine aggregate shall consist of clean, sound, durable particles of crushed stone, durable particles of crushed
stone, slag, or gravel. The aggregate shall meet its requirements for stripping, abrasion resistance and percent
friable particles as specified for coarse aggregate.
2.3 ANTISTRIPPING AGENT
The use of antistripping agent is subject to prior approval by the Contracting Officer.
2.4 EMULSIFIED ASPHALT FOR FOG SEAL
NOTE: In the majority of applications, the cationic (CSS-1h) is preferable
to the anionic (SS-1h) for use as fog seal. Cationic emulsion will cure at
a faster rate than anionic and is more suitable where high humidity prevails.
Anionic emulsions possess a negative charge on the asphalt droplets and cationic
emulsions carry a positive charge on the asphalt droplets. All aggregate possess
a negative surface charge at their natural pH. This negative surface charge
varies in intensity depending on the geological source of the aggregate.
Emulsified asphalt for Fog Seal shall conform to ASTM D 977, [SS-1] [SS-1h] [_____] for anionic and ASTM D 2397
[CSS-1] [CSS-1h] [_____] for cationic materials.
2.5 WATER
Provide fresh, clean, and potable water.
PART 3 EXECUTION
3.1 PREPARATION OF SURFACE
NOTE: If the surface to be treated requires repairs, the method of repairs
and extent of work involved should be shown or described.
Removal of paint and rubber deposits are generally accomplished by high pressure
water blasting. Few approved chemicals are effective and sandblasting is not
permitted by air pollution regulations at some locations. Mechanical abrasion
generally causes damage to the pavement.
Bracketed sentence at the end of this paragraph applies to Fog Seal; remove
when not used in the project.
Repair damaged surface and fill cracks before starting work. Immediately before starting work, remove all loose
material, dirt, clay, or other objectionable material from the surface to be treated with power brooms or power
blowers, if needed. Paint firmly bonded to the surface that has the chalk removed may remain. Material removed
from the surface shall not be mixed with the cover aggregate.[ When necessary to achieve a clean surface for
fog application, flushing with water will be permitted.]
3.2 SEAL COAT APPLICATION
3.2.1 Rate
Spread the bituminous material in the quantities shown in TABLE III. The exact quantities within the range specified,
which may be varied to suit field conditions, will be determined by the Contractor and approved by the Contracting
Officer prior to use.
TABLE III. APPLICATION OF MATERIAL
(Quantities Per Square Meter)
Gradation
No. Bitumen, liters Aggregate, kilograms
__________ ________________ _____________________
1 0.60-0.90 8-10
2 0.45-0.60 5-8
3 0.45-0.60 5-8
TABLE III. APPLICATION OF MATERIAL
(Quantities Per Square Yard)
Gradation
No. Bitumen, gallons Aggregate, pounds
__________ ________________ _________________
1 0.15-0.20 15-20
2 0.10-0.15 10-15
3 0.10-0.15 10-15
3.2.2 Temperature
[Asphalt application temperature shall provide an application viscosity between 10 and 60 seconds, Saybolt Furol,
or between 20 and 120 square mm/sec 20 and 120 centistokes, kinematic. Furnish the temperature viscosity relation
to the Contracting Officer.] [Tar application temperature shall be within the following ranges as directed:]
RT-6 -------------------- 26-65 degrees C 80-150 degrees F
RT-7 -------------------- 65-107 degrees C 150-225 degrees F
RT-8 -------------------- 65-107 degrees C 150-225 degrees F
RT-9 -------------------- 65-107 degrees C 150-225 degrees F
RT-10 -------------------- 52-120 degrees C 125-250 degrees F
RT-11 -------------------- 52-120 degrees C 125-250 degrees F.
3.2.3 Application of Bituminous Material
Following the preparation and inspection of the pavement surface, apply the seal coat material at the specified
rates. Uniformly apply the bituminous material in a single pass of the distributor and with either a double
or triple lap spray over the surface to be sealed. Spread building paper on the surface for a sufficient distance
back from the ends of each application so that flow through the spray bar may be started and stopped on the paper
and so that all sprays will be operating at the proper pressure on the surface to be sealed. Immediately after
the application, remove the building paper. Properly treat with bituminous material spots missed by the distributor.
No smoking, fires, or flames, other than the heaters that are a part of the equipment, will be permitted within
8 meters 25 feet of heating, distributing, and transferring operations of bituminous material other than bituminous
emulsions. [If tar is used, a full-face organic vapor-type respirator and protective creams shall be used by
personnel exposed to fumes. Protective creams shall not be used as a substitute for cover clothing.]
3.2.4 Aggregate Application Rate
Spread the aggregate in the quantities shown in TABLE III. The exact quantities within the range specified,
which may be varied to suit field conditions, will be determined by the Contractor, and approved by the Contracting
Officer prior to use. The aggregate weights shown in this table are those of aggregate having a specific gravity
of 2.65. If the specific gravity of the aggregate to be used is less than 2.55 or greater than 2.75, make adjustments
in the number of pounds of aggregate required per square yard to insure a constant volume of aggregate per square
yard of treatment.
3.2.5 Application of Aggregate
NOTE: When using cutback asphalt, the asphalt cools to the temperature of the
surface to which it is applied in approximately 1 1/2 minutes. In the case
of emulsified asphalt, breaking of the emulsion occurs in 3 to 4 minutes. No
bituminous material should be down more than the following number of minutes
before it is covered with aggregate:
1 - 1 1/2 Minutes for cutback asphalt
3 - 4 Minutes for emulsified asphalt
1 Minute for asphalt cement
Spread the specified quantity of cover aggregate uniformly over the bituminous material. Before the bituminous
material is applied, sufficient aggregate to cover the distributor load of bituminous material shall be on trucks
at the site of the work. No bituminous material shall be down more than 3 minutes before it is covered with
aggregate. Spreading shall be done uniformly with aggregate-spreading equipment. Trucks spreading aggregate
shall be operated backwards, covering the bituminous material ahead of the truck wheels. Areas having insufficient
cover shall be lightly recovered with additional aggregate by hand during the operations whenever necessary.
3.2.6 Rolling and Brooming
Begin rolling operations immediately following the application of cover aggregate. Perform rolling using pneumatic-tired
rollers. Operate the rollers at a speed that will not displace the aggregate. Continue rolling until the aggregate
is uniformly distributed and keyed into the bituminous material. All surplus aggregate shall be swept off the
surface and removed not less than 24 hours nor more than 4 days after rolling is completed.
3.3 FIELD QUALITY CONTROL - SEAL COAT
3.3.1 Tests
Perform field tests in sufficient numbers to assure that the specifications are being met. Testing is the responsibility
of the Contractor and shall be performed by an approved commercial laboratory. The following number of tests,
if performed at the appropriate time, will be the minimum acceptable for each type of operation.
3.3.1.1 Gradation
Perform gradation tests in accordance with ASTM C 136. Perform a minimum of one gradation for every [_____]
[metric tons tons] [cubic meters cubic yards] of aggregate to be placed, with a minimum of three gradations for
each day's run. When [the source of materials is changed or] deficiencies are found, the gradation shall be
repeated and the material already placed shall be retested to determine the extent of the unacceptable material.
Replace all in-place unacceptable material at no additional expense to the Government.
3.3.1.2 Abrasion Resistance
Perform abrasion resistance tests in accordance with ASTM C 131. Perform one test for every [_____] [metric
tons tons] [cubic meters yards] of aggregate placed.
3.3.1.3 Stripping
Perform stripping test on aggregate from each source, in accordance with ASTM D 3625, prior to incorporation
into the work and when the source is changed.
3.3.2 Bituminous Material Sample
Obtain a sample of the bituminous material used under the supervision of the Contracting Officer. The sample
will be retained by the Government.
3.4 TRIAL APPLICATION - SEAL COAT
Prior to applying the seal coat, place a test section at least 30 meters 100 feet long by 6 meters 20 feet wide
using the approved job materials and roll them in accordance with the specified requirements. Perform tests
to determine the application rates of the bitumen and aggregate. If the tests indicate that the seal coat test
section does not conform to the specification requirements, make necessary adjustments to the application equipment
and to the spreading and rolling procedures, and construct additional test sections for conformance to the specifications.
Where test sections do not conform to specification requirements, remove seal coat at no expense to the Government;
no separate payment will be made for seal coat materials and labor, either in placement or removal of any test
section. Perform quality control sampling and testing during construction as required in paragraph FIELD QUALITY
CONTROL above.
3.5 FOG SEAL APPLICATION
3.5.1 Sample Application
NOTE: In some localities an incompatibility may exist between the asphaltic
emulsion and the water to be used for dilution due to their characteristics.
Clear, potable water should be used, and if there is any doubt with the compatibility
of the water and the asphalt emulsion, add the following to this paragraph:
Prior to commencing work, 0.24 liter (one half pint) of the proposed asphalt
emulsion and 0.24 liter (one half pint) of the proposed water shall be combined,
agitated, and allowed to sit for a period of 24 hours to test their compatibility.
If they prove to be incompatible, an approved chemical treatment shall be provided
for all water used for dilution or a different and compatible source of water
shall be selected.
Determine the required application rate from a sample installation. Select an area of the prepared pavement
at least 90 m 300 feet long and as wide as the distributor spray bar. Dilute emulsified asphalt with an equal
part of water or as recommended by the manufacturer. Apply the water diluted asphalt emulsion in at least three
test sections; each a minimum of 30 m 100 feet long. The trial applications shall be made at the rates of [0.36]
[_____], [0.63] [_____], and [0.90] [_____] L/square meter [0.08] [_____], [0.14] [_____], and [0.20] [_____]
gallons/square yard. The trial application rates may be modified if approved by the Contracting Officer. Additional
trial applications may be made if warranted by pavement surface conditions. Use the rate which has been satisfactorily
applied without leaving an excess of asphalt residue on the surface and has been approved, for the fog seal.
3.5.2 Application Inspection
Inspect application of fog seal for uniformity. [During application, take [_____] sample for each [400] [_____]
square meters [500] [_____] square yards of surface area to receive emulsified asphalt. Weigh samples to determine
conformance with application rate.]
3.5.3 Inspection Reports
Furnish a written report citing climatic temperature during application, emulsion temperature during application,
and rate of emulsion application.
3.5.4 Application
Following preparation of the surface, apply the water diluted asphalt emulsion at the rate determined from the
trial application. Maintain application temperature of emulsified asphalt between 24 and 71 degrees C 75 and
160 degrees F. To obtain uniform application of the fog seal at the junction of previous and subsequent applications,
spread building paper on the surface of the applied material for a sufficient distance back from the ends of
each application so that flow from the spray bar may be started and stopped on the paper, and so that all sprayers
will operate at full force. Immediately after application, remove and properly dispose of the building paper.
Treat spots unavoidably missed with the hand spray equipment. Base bids on application of diluted emulsion at
0.63 L/square meter 0.14 gsy. If the actual amount required is more or less than 0.63 L/square meter 0.14 gsy
, an adjustment in the contract price will be made as provided by the contract.
3.6 SITE PROTECTION
During applications, protect adjacent buildings, structures, vehicles, manhole covers, inlet grates, and trees
to prevent being spattered or marred.
3.7 TRAFFIC CONTROL
Protect freshly placed coatings from damage by traffic. Provide sufficient warning signs and barricades to prevent
traffic over freshly treated surfaces. Protect treated areas from traffic for at least [2] [24] hours after
final application of coatings, or for such time as necessary to prevent picking up. Immediately prior to opening
to traffic, roll the entire treated area with a self-propelled pneumatic-tired roller. Provide warning signs
and barricades for proper traffic control, in accordance with MUTCD.