Cape_Seal_Specifications.docx

Cape Seal Specifications

Description A Cape Seal is a surface treatment in which a chip seal interlayer course is followed by a Micro-Surfacing wearing course. The Micro-Surfacing course shall be applied no sooner than 7 calendar days later the chip seal application. The Micro-Surfacing course shall be applied during the same construction season as the chip seal interlayer course.

Materials

1. Liquid Asphalt: Liquid asphalt grades shall be: CRS-2 or RS-2 conforming to AASHTO specifications M208 or M140. The liquid asphalt shall be compatible with the aggregate to be utilized for the chip seal interlayer course.

2. Stone: Stone shall be crushed quarry stone, free from dust, soft stone or other contaminants with a minimum of 70% of the stones having a fractured face. All stone shall satisfy a 35% maximum for the L.A. Abrasion Test and a 35% maximum for the Flakiness Index Test. Stone shall be treated prior to application with liquid asphalt material at the rate of 0.2% to 0.5% residual asphalt to ensure uniform treatment of all stones. Proper pre-treatment shall be obtained by a twin-shafted pugmill with a digital readout belt scale.

Required Stone Gradation 9.5mm (3/8”) Stone

Application The quantity of asphalt material to be used shall be in the range of 0.35 to 0.50 gallons per square yard. Cover aggregate shall be spread in the range of 20 to 30 pounds per square yard. The winning bidder will use lab tests and current chip seal design standards to design specific material quantities to meet existing field conditions. The chip seal design shall be submitted to the program participant for approval prior to starting the work. Variations in material quantities will be made without adjustment to contract unit price.

Equipment

1. Asphalt Distributor: The asphalt distributor shall contain suitable mechanical circulating and heating mechanisms to provide a uniform approved temperature of the entire mass of material. The distributor shall be equipped with a radar type sensor used to measure ground speed and feed a Digital Volumetric Accumulator capable of measuring gallons applied and distance traveled. It shall be capable of applying asphalt material in accurately measured quantities at any rate between 0.1 to 2.0 gallons per square yard of roadway surface, at any length of spray bar up to 12’ feet. The distributor shall be capable of maintaining a uniform rate of distribution of asphalt material regardless of change in grade, width or direction of the road. It shall be equipped with an electronic control for setting asphalt pump discharge rate and on/off switching of spray for nozzles in one (1’) foot increments which shall be located in the truck cab. The spray nozzles and pressure system shall provide a sufficient and uniform fan-shaped spray of asphalt material throughout the entire length of the spray bar at all times while operating. The spray shall completely cover the roadway surface receiving the treatment.

2. Aggregate Spreader: The aggregate spreader shall be hydrostatically driven and self-propelled. It may be equipped with a hydraulically controlled variable adjustable head that is capable of spreading stone in widths from 4.5’ to 12’ feet. The spreader shall be mounted on pneumatic tires and shall apply the stone on the road surface in a manner that ensures that the tires do not contact the road surface until after the stone has been applied. The u At least two rubber tired rollers shall be used on each treated surface immediately after the stone has been applied. Each roller shall have a compacting width of not less than 5’ feet. Each roller shall have a gross weight of not less than 8 tons and contact pressure adjustable from 200 to 300 psi.

3. Rollers: At least two rubber-tired rollers shall be used on each treated surface immediately after the stone has been applied. Each roller shall have a compacting width of not less than 5 feet. Each roller shall have a gross weight of not less than 8 tons and contact pressure adjustable from 200 to 300 PSI.

4. Trucks: Rear discharge conveyor-fed trucks in sufficient number and size must be used to deliver stone to spreader.

Construction Methods

1. Surface Preparation: Surface preparation, which may include patching and adjusting of drainage and utility structures, may be completed under other items on this contract prior to the chip seal treatment. Any other surface preparation required that is not covered under an item on this contract will be the responsibility of the participant. Immediately prior to surface treatment, the roadways shall be swept of any loose debris by use of a mechanical sweeper. Sweeping in advance of the chip seal application may be done by the participant or by the winning bidder and paid hourly under this contract. Participant is responsible for the disposal of swept material, unless otherwise specified in the contract.” The winning bidder shall protect any manhole covers, drop inlets, catch basins, curbs, and any other structures that will be affected by the surface treatment application.

2. Weather Limitations: Work will not be done unless the road surface is free of standing water. No work shall be done during rain or foggy periods. No works hall be done if the ambient temperature is below 50° F.

3. Spreading Asphalt and Stone: Prior to application of asphalt material on any street, sufficient quantities of materials to cover the entire street at the specified rates shall be on the site and ready for application. The participant shall be responsible for providing the winning bidder with an aggregate storage area near the job site. The asphalt material shall not be applied more than 300’ feet in advance of the self-propelled aggregate spreader. At no time shall any asphalt material be on any road surface for more than fifteen seconds before it is covered with stone.

4. Rolling: Initial rolling shall be done immediately following the application of the treated stone. Rollers shall be operated at a speed that will not displace aggregate.

5. Final Sweeping: Surplus aggregate shall be swept off the road surfaces by the chip seal contractor in advance of Micro-Surfacing after stone seal has properly cured. In no case shall initial sweeping occur more than 10 days after the chip seal application. Participant is responsible for the disposal of swept material, unless otherwise specified in the contract.

Micro-Surfacing Course Micro-Surfacing shall be applied over the chip seal interlayer course in the same season but no sooner than seven (7) days after chip seal application. After Micro-Surfacing has been applied, the cape seal will be complete.

Traffic Control Suitable methods shall be used by the winning bidder to protect the micro-surface from traffic until the new surface will support traffic without damage. All traffic control methods used shall be in accordance with the Engineer’s specifications and shall be employed in a safe manner. The cost of flaggers and any police details, if required, will be paid or reimbursed by the participant. The participant will coordinate detail assignments which will be billed to the contractor directly based on the hourly cost. The winning bidder will not be reimbursed for police detail expenses incurred due to failure to cancel or cancelling without the required notice.

Measurement and Payment The quantity to be measured for payment will be the number of square yards of Cape Seal actually completed, and this quality shall be determined and verified daily. The accepted quantity of Cape Seal will be paid for at the contract unit price per square yard of the type specified in the proposal, which shall be full compensation for furnishing, transportation, handling and placing the material specified and furnishing of all labor, tools, equipment, and incidentals for the satisfactory completion of this item.