330 Page 196330 PRIME, TACK, FOG SEAL, AND FLUSH SEAL
330.1DESCRIPTION
This work consists of preparing and treating a prepared surface with asphalt material and sand as required.
330.2MATERIALS
Materials will conform to the following Sections: A.Asphalt: Section 890. B.Blotting Sand for Prime: Section 879. C.Sand for Flush Seal: Section 879. D.Sand for Fog Seal: Section 879.
330.3CONSTRUCTION REQUIREMENTS
A.Weather and Seasonal Requirements: Application will be made only during daylight hours, when the wind does not adversely affect the spraying operation and when the following conditions are met: 1.Asphalt for Prime: The application of asphalt for prime will be permitted only: a.When the ambient air and surface temperatures on the project are both at least 60F in the shade. b.When conditions are dry. When plans call for prime on interim surfacing, the prime application will closely follow the base finishing operation and at no time will the prime operation be more than 3 miles from the base finishing operation. The cure time for the processed base, prime, and blotting sand application will be determined by the Engineer. Surfaces primed with cutback asphalt will be allowed to cure for a minimum of 72 hours prior to being overlaid with asphalt concrete. 2.Asphalt for Tack: The application of asphalt for tack will be permitted only: a.When the ambient air and surface temperature on the project are both at least 35F in the shade. b.When conditions are dry, except emulsified asphalt may be applied when the surface is slightly damp. 330 Page 1973.Asphalt for Fog Seal: The application of asphalt for fog seal will be permitted only: a.When the ambient air and surface temperature on the project are both at least 60F in the shade. b.When conditions are dry. c.Fog seal application will begin after the asphalt surface treatment is cured and will not begin prior to completing final brooming. Fog seal application will be completed no later than 7 calendar days following asphalt surface treatment application. 4.Asphalt for Flush Seal: The application of asphalt for flush seal will be permitted only: a.Between May 1 and November 1, inclusive. b.When ambient air and surface temperatures on the project are both at least 50F in the shade. c.When the surface is dry or slightly damp. B.Dilution of Tack, Fog Seal, and Flush Seal: Emulsified asphalt for tack, fog seal, and flush seal with a specified application rate of 0.07 gallons per square yard or less may be diluted. The rate of dilution for tack will be at a ratio of at least 1 part emulsion to no more than 1 part added water (1:1 ratio minimum) by volume, unless otherwise approved by the Engineer. The rate of dilution for fog seal and flush seal will be at a ratio of not more than 3 parts emulsion to 1 part added water (3:1 ratio maximum) by volume to not less than 1 part emulsion to 1 part added water (1:1 ratio) by volume, unless otherwise approved by the Engineer. The emulsion will be uniformly mixed by adding potable water and if necessary, agitating the mixture. The amount of emulsion and any added water will be included on the ticket delivered to the project. If the emulsion is diluted, the emulsified asphalt supplier will perform the dilution. Dilution of asphalt emulsion in the field will not be allowed unless approved by the Engineer. Field dilution of the emulsified asphalt will only be allowed when the rate of dilution is accurately controlled and reported to the Engineer. Field dilution will be performed as recommended by the emulsified asphalt supplier. The final rate of dilution will not be less than the minimum ratio of at least 1 part emulsion to no more than 1 part added water (1:1 ratio minimum). Diluted emulsified asphalt for tack, fog seal, and flush seal will be applied at an adjusted rate proportional to the dilution ratio resulting in application of the specified rate of emulsion. Emulsified asphalt for tack, fog seal, or flush seal with a specified rate exceeding 0.07 gallons per square yard will not be diluted. 330 Page 198The storage tank for diluted emulsified asphalt must utilize a recirculation system or agitator that will prevent settlement or separation of the material. C.Equipment: The following minimum equipment will be furnished by the Contractor. 1.Brooms: a.Pickup Broom: In curb and gutter sections or in rural sections where a finished and maintained lawn extends to the edge of the shoulder, the Contractor must use a pickup broom with an integral self-contained storage. The pickup broom must be a minimum of 6 feet wide. The sweeping operation must remove all loose material, including loose material from the gutter. b.Rotary Power Broom: A rotary power broom may be used in all other areas. 2.Heating Equipment: Equipment for heating the asphalt material in or at the tank car, transport truck, or distributor will be designed and constructed to heat the material without burning, scorching, or overheating, and with positive control of the heat. The introduction of steam directly into the material will not be permitted. 3.Distributors: Distributors used to apply the asphalt material will be self-propelled, equipped with pressure type mechanical circulating pumps and valves, a heating system and insulated tank, which will provide the uniform required temperature throughout the entire contents of the distributor tank. The distributor will have a capacity of at least 800 gallons. Detachable distributor units separate from the tank will not be allowed. The distributor will uniformly apply the heated asphalt material to the road surface in accurately measured quantities and maintain the specified rate of application during the distribution of the entire tank-load, regardless of change in gradient, superelevation, direction, or content level in the tank. Calibration runs for verification will be made at the start of the work. The spray nozzles will be designed, sized, and arranged to ensure uniform distribution of heated asphalt material at the designated rate, in an overlapping fan shaped spray without surge, streaks, ridges, or bare spots. A strainer will be provided in the discharge line to prevent nozzles from clogging. The output of each and every nozzle on the bar will be the same and a test will be made, in advance of use to determine compliance with this requirement. Different sizes, heights, pressures, and settings of nozzles for different designated rates will be provided. The distributor will be equipped with a tachometer, clearly visible to the operator, which accurately shows the speed in feet per minute. Pressure metering distributors will be furnished with an accurate pressure gauge showing the distribution pressure. Volume metering distributors will be furnished with a pump tachometer or meter showing the volume furnished. The distributor will include an accurate, mercury actuated thermometer showing the temperature of the material in the tank and a contents gauge showing the number of gallons in the tank at any content level. 330 Page 199The distributor will be equipped with adjustable spray bars arranged so the application width will be available in 2 foot intervals. The distributor spray bars will be capable of operating at a constant controlled height and will be of the full circulating type. Each nozzle of the distributor bar will be equipped with a cutoff valve, which immediately stops the flow without dripping. Compliance with these requirements must be proven before the distributor can be used. D.Surface Preparation: The surface will be thoroughly swept and cleaned of all foreign material. Appurtenances immediately adjacent to the surface to be treated will be protected from the splatter of asphalt. Manhole covers, water shut valves, and other utility access points will be covered to ensure liquid asphalt is not applied to them, as directed by the Engineer. Surfaces to receive a prime coat will be satisfactorily compacted and cured. E.Application of Asphalt: During application the temperature of the asphalt will be maintained within the temperature range furnished by the asphalt supplier. Asphalt will be applied by a pressure distributor in a uniform and continuous manner. Coverage will be made to the satisfaction of the Engineer. Unauthorized increases in rate of application will not be eligible for payment. The angle of the spray nozzles and the height of the spray bar will be set to obtain uniform distribution. The distributor will travel at the established speed when the spray bar is opened. Areas inaccessible to the distributor will be covered by hand spray methods. When the distributor is not in operation, it will be parked off the roadbed or drip pans will be placed under the spray bar. The tack coat will be allowed to break (turn from brown to black) and will be allowed a cure period, as determined by the Engineer, ahead of mat laydown. Tack application ahead of mat laydown will be limited by job conditions and will not exceed the amount estimated for the current day's operation. Tacked areas, which become unsatisfactory as a result of traffic, weather, or other conditions, will be retacked. Required retacking which is not the fault of the Contractor will be paid for at the contract unit price for tack asphalt. F.Application of Sand: Blotting of prime will be accomplished by broom sweeping or spreading sand on the primed surface with a mechanical spreader. Hand spreading will be permitted on odd shaped or inaccessible areas. Application of sand will not be permitted until the prime has set for at least 24 hours, unless otherwise directed by the Engineer. The fresh application of asphalt for flush seal will be covered with a uniform spread of sand immediately behind the distributor. The sand will be placed by a self-powered aggregate spreader with positive controls or other equipment acceptable to the Engineer. The sand will be placed uniformly on the asphalt application. Rolling will not be required. The finished surface will be smooth riding without transverse or longitudinal ridges and will present a uniform satisfactory appearance. Bleeding areas will be resanded. Rough and nonuniform areas will be corrected. When applying fog seal coats, a light application of sand may be ordered by the Engineer to prevent material pick up. If ordered, the sand will be placed by a self-powered aggregate 330 Page 200spreader with positive controls or other equipment acceptable to the Engineer. The sand will be placed uniformly on the asphalt application. Rolling will not be required. The finished surface will be smooth riding without transverse or longitudinal ridges and will present a uniform satisfactory appearance. Bleeding areas will be resanded. Rough and nonuniform areas will be corrected. The loose sand material remaining on the surface will be lightly broomed off after a waiting period of twenty-four hours from the time of application or as otherwise directed by the Engineer. Excess material in curb and gutter sections will be broomed towards the gutter and will be picked up and disposed of by the Contractor. Unauthorized increases in rate of application will not be eligible for payment. G.Temporary Traffic Control: The Contractor will provide flaggers, signs, and barriers to warn, direct, and prevent traffic from traveling on the freshly applied asphalt until it has penetrated, and does not track or pickup on the tires of traveling vehicles or the surface has been blotted with sand. Temporary traffic control will conform to Section 634.
330.4METHOD OF MEASUREMENT
A.Asphalt: Asphalt will be measured to the nearest 0.1 ton. B.Blotting Sand for Prime: Blotting sand for prime will be measured to the nearest 0.1 ton. C.Sand for Flush Seal: Sand for flush seal will be measured to the nearest 0.1 ton. D.Sand for Fog Seal: Sand for fog seal will be measured to the nearest 0.1 ton.
330.5BASIS OF PAYMENT
A.Asphalt: Asphalt will be paid for at the contract unit price per ton complete in place. Separate payment will not be made for water for dilution of emulsified asphalt. B.Blotting Sand for Prime: Blotting sand for prime will be paid for at the contract unit price per ton complete in place. Payment will be full compensation for furnishing, installing, and all incidentals required to complete the work. C.Sand for Flush Seal: Sand for flush seal will be paid for at the contract unit price per ton complete in place. Payment will be full compensation for furnishing, installing, and all incidentals required to complete the work. D.Sand for Fog Seal: Sand for fog seal will be paid for at the contract unit price per ton complete in place. Payment will be full compensation for furnishing, installing, and all incidentals required to complete the work. 332 Page 201332 COLD MILLING ASPHALT CONCRETE
332.1DESCRIPTION
This work consists of cold milling a portion of the existing asphalt concrete surface course and hauling and stockpiling the removed material.
332.2MATERIALS
Cold milled asphalt concrete will conform to the requirements of Section 884.
332.3CONSTRUCTION REQUIREMENTS
A.General: The material will be removed by cold milling with the specified equipment, without the use of heat. The Contractor will not dispose of cold milled asphalt concrete material or use the cold milled material for any purpose other than purposes designated in the plans without approval by the Engineer. B.Equipment: The equipment for cold milling will consist of a rotating drum equipped with teeth capable of removing material to a depth of up to 3 inches in one pass, producing a uniform surface finish. The cold milling machine will establish a longitudinal profile grade within ±1/8 inch referenced from a traveling stringline or erected fixed string line and will be controlled by an automatic system for controlling grade. The cold milling machine will be equipped so that the depth and transverse slope of the drum is manually or automatically controlled using the traveling or fixed stringline on either or both sides of the milling machine. The fixed stringline will remain taut after being tightened. The traveling stringline will have a minimum effective length of 28 feet. The traveling stringline will be attached and positioned on the milling machine to reference the longitudinal profile. The traveling stringline will utilize either mechanical skis or non-contacting grade averaging sensors. If mechanical skis are provided, the sensor of the control system will rest midway between the traveling stringline. Following milling of the first pass, adjacent passes will be milled referencing the traveling stringline riding on the previously milled pass or a fixed stringline. A shoe attachment may be used to match an adjacent reference point when directed by the Engineer. The drum will be capable of tilting to allow feathering of edges to zero cut. C.Construction Methods: The existing surface of the pavement will be removed by milling to the depth, width, cross section, and grade specified. The resulting milled surface will be free of detrimental ridges or grooves. The final pavement surface will have a transverse pattern of 3/4 inch center to center of each strike area. The difference between the ridge and valley of the mat surface will not exceed 1/4 inch when tested in accordance with SD 320.