360 Page 207360 ASPHALT SURFACE TREATMENT
360.1DESCRIPTION
This work consists of an application of asphalt covered with a spread of cover aggregate.
360.2MATERIALS
A.Asphalt: Asphalt will conform to Section 890. B.Cover Aggregate: Cover aggregate will conform to Section 881.
360.3CONSTRUCTION REQUIREMENTS
A.Weather and Seasonal Requirements: Surface treatment operations will be permitted only during daylight hours, when conditions are dry, when wind does not adversely affect the spraying operation, and when overnight low air temperatures within 24 hours of the planned application are forecasted to be at least 45°F. Minimum temperatures and seasonal limitations are as follows: Minimum Temperature and Seasonal Limitations Cover AggregatesAir and Surface Temperature (in the shade and rising)Seasonal Limitations (dates are inclusive) Type 1 60°F May 15 – Aug. 31 Type 2 60°F May 15 – Aug. 31 Type 3 60°F May 15 – Sept. 15 B.Equipment: The following equipment will be furnished: 1.Broom: 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 will use a pickup broom with an integral self-contained storage. The pickup broom must be a minimum of 6 feet wide. While sweeping in curb and gutter sections, 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.Equipment for heating and applying the asphalt conforming to the requirements of Section 330.3 C. 3.A self-propelled aggregate spreader, with positive controls capable of depositing the required quantity of aggregate uniformly over the full width of the asphalt application. 4.A minimum of four self-propelled pneumatic smooth tired rollers for each spreader in use. Each roller will completely cover an overall surface width of at least 60 inches and furnish a minimum uniform rolling weight (mass) of 250 pounds per of rolling width. 360 Page 208C.Cover Aggregate Preparation: Following production of the cover aggregate stockpile and at least 14 calendar days prior to starting the asphalt surface treatment, the Contractor will submit a sample of the cover aggregate to the asphalt supplier for evaluation of compatibility and design of the surface treatment. Prior to starting the surface treatment, the Contractor will submit a copy of the compatibility test results and the asphalt surface treatment design from the asphalt supplier to the Engineer and the Department’s Bituminous Engineer. The Contractor will notify the Area Office a minimum of 5 calendar days prior to sampling and submitting the cover aggregates. Satisfactory quality test results for the cover aggregate will be obtained prior to use on the project. 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. The Contractor will repair any damage to the satisfaction of the Engineer at no additional cost to the Department. 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. The methods used for covering will be removed after completion of the final asphalt surface treatment application. Freshly primed bases will be cured prior to the application of surface treatments. The Contractor will ensure transverse rumble strips are not damaged or otherwise modified to lose their functionality during the application of the surface treatment. The Contractor will only apply a fog seal to the rumble strips. The Contractor will repair any damage or loss of functionality of rumble strips to the satisfaction of the Engineer at no additional cost to the Department. E.Application of Asphalt: The asphalt will be maintained within a temperature range of 120F to 180F during application. Asphalt will be applied by a pressure distributor in a uniform and continuous manner. Unauthorized increases in the asphalt application rate 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. When starting and stopping emulsion application, a strip of building paper or other suitable material, at least 3 feet in width and at least 1 foot longer than the width of the spray bar, will be used to prevent a double application of emulsion. The distributor will travel at the established speed when the spray bar is opened. Skipped areas and deficiencies will be immediately corrected. Areas inaccessible to the distributor will be satisfactorily covered by hand spray methods. Spraying operations will not proceed when it is evident the asphalt spread will not be covered with aggregate and rolled all in accordance with the prescribed schedule. F.Application of Cover Aggregate: Cover aggregate will be spread immediately following application of all rapid-setting emulsions. For wind conditions of 5 miles per hour or less, the cover aggregate will be spread within 5 minutes of the application of the medium-setting emulsion. For wind conditions greater than 5 miles per hour, the time may be reduced in the field to ensure the aggregate is applied before the medium setting emulsion breaks. Time 360 Page 209limits for spreading of cover aggregate when using medium-setting emulsions will be adjusted as directed to satisfy project conditions. The aggregate will be applied before the emulsion begins to break (emulsion still brown in color). A complete aggregate coverage will be continually maintained. A strip of asphalt application approximately 6 inches wide for a double overlap spray bar or 8 inches wide for a triple overlap spray bar, along that side of the spread forming a longitudinal joint with the adjacent spread will be left uncovered. The adjacent asphalt and cover aggregate application will overlap this strip. In lieu of this procedure a butt joint may be constructed using special end nozzles. Longitudinal joints, other than at centerline, will not be permitted within the center 24 feet unless otherwise approved by the Engineer. When loading trucks, the Contractor will screen the cover aggregate to minimize segregation, eliminate oversize, reduce aggregate dust, and effectively break up or discard material bonded into chunks. At the discretion of the Engineer, if the cover aggregate does not prove the need for screening, the screening requirement may be waived provided all test results and visual inspections produce satisfactory results. If segregation, oversize material, excessive dust, or material bonded into chunks becomes evident during cover aggregate placement, the Contractor will immediately resume screening of the cover aggregate. When required, aggregate will be uniformly moistened before or during loading. Unauthorized increases in application rates will not be eligible for payment. Prior to rolling, the contractor may be directed to adjust inequalities in the spread of Type 3 cover aggregate with a drag broom. G.Rolling: Rolling will begin immediately behind the spreader and will consist of four complete coverages using pneumatic tired rollers. A complete coverage is defined as rolling full width in one direction. The rolling will be completed within 40 minutes after the cover aggregate is applied. Rollers will be operated in unison at a close interval, and if the width of spread allows, in a staggered formation. Rollers will not be operated at a speed in excess of 5 miles per hour. Asphalt and cover aggregate applications will not extend more than 1/2 mile beyond the rolling operation. With the use of minimum specified equipment, the project will be completed in 1/2 mile increments, except for the sweeping of excess cover aggregate. The weight and tire pressures of the rollers will be varied as directed to obtain optimum embedment of the cover material without undue crushing of the aggregate. Special attention will be given to the transverse and longitudinal joints during rolling. Unsatisfactory joints will be corrected without additional compensation. Turning of rollers on the freshly treated surface is prohibited. Rolling at night or when light conditions would create a traffic hazard will not be allowed. H.Traffic Control : Construction operations will be coordinated to minimize traffic delays. One-way traffic will be maintained during application of the surface treatment on driving lanes. Upon completion of rolling, traffic will be permitted to travel on the treated surface. Traffic will be controlled by pilot cars and flaggers during application of the surface treatment on driving lanes with the speed of pilot cars not to exceed 20 miles per hour on the freshly applied surface treatment for a period of at least 1 hour after application or until the asphalt surface 360 Page 210treatment is sufficiently cured. Prior to moving the pilot car operation from the section of roadway, the Contractor will perform initial brooming in accordance with Section 360.3 I. The width, arrangement, and sequence of the parallel application strips will not unduly inconvenience traffic. I.Brooming: In curb and gutter sections and in areas where a finished and maintained lawn extends to the edge of the shoulder, the loose material will be swept up with a pickup broom. 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. Brooming the material into a pile with a rotary broom for pickup will not be allowed. In sections without curb and gutter and in areas where a finished and maintained lawn does not extend to the edge of the shoulder, the loose material may be swept onto the roadway inslopes, as approved by the Engineer. Broomed off material picked up by the Contractor will be disposed of at sites provided by the Contractor and approved by the Engineer. 1.Initial Brooming: The Contractor will perform initial brooming while traffic is maintained as described in Section 360.3 H. Initial brooming will consist of a light brooming of the surface to remove loose chips. The initial brooming will not cause damage to the asphalt surface treatment. If initial brooming causes damage to the asphalt surface treatment, the Engineer, in the Engineer’s discretion, may require the Contractor to alter the initial brooming operation or to waive the initial brooming requirement. 2.Final Brooming: The Contractor will perform final brooming during a cool period of the following morning, within 24 hours of application, to remove all loose material remaining on the surface. The brooming will include the entire surface of the asphalt surface treatment application, additional lane widths, intersections, and shoulders. J.Maintenance and Repair: Areas of the surface treatment, which peel or are otherwise unsatisfactory, will be repaired with additional asphalt, cover aggregate, and rolling. Compensation for repairs due to causes beyond the control of the Contractor will be paid at the contract unit price for asphalt surface treatment. The finished surface treatment will be uniform and smooth riding. Transverse or horizontal ridges, raveled spots, wheel marks, depressions, abrupt color changes, and other inequalities will be corrected. Payment will not be made for this correction work. Asphalt splattered on roadway appurtenances will be satisfactorily cleaned off by the Contractor.
360.4METHOD OF MEASUREMENT
A.Asphalt for Surface Treatment: Asphalt for surface treatment will be measured to the nearest 0.1 ton. B.Cover Aggregate: Cover aggregate will be measured to the nearest 0.1 ton. 360 Page 211360.5 BASIS OF PAYMENT A.Asphalt for Surface Treatment: Asphalt for surface treatment will be paid for at the contract unit price per ton. B.Cover Aggregate: Cover aggregate specified will be paid for at the contract unit price per ton. Payment will be full compensation for furnishing, installing, and all incidentals required to complete the work. 370 Page 212370 COLD IN PLACE RECYCLING (CIR) OF ASPHALT CONCRETE
370.1DESCRIPTION
This work will consist of milling asphalt pavement, mixing the reclaimed asphalt pavement (RAP) material with emulsified asphalt, placing the recycled mixture, and compacting the recycled mixture according to these specifications and the typical sections in the plans.
370.2MATERIALS
A.Reclaimed Asphalt Pavement (RAP): Section 884. B.Asphalt: Section 890.
370.3CONSTRUCTION REQUIREMENTS
A.Rollers: Pneumatic tired rollers will have an effective roller weight (mass) of at least 250 pounds per inch of roller width or satisfactory vibratory compaction equipment. Tires will be uniformly inflated so their air pressures will not vary by more than 5 psi. Rollers will be operated with tire pressures and wheel loads within the manufacturer’s recommended range for the size and ply of the tire being used. Steel rollers will furnish a minimum rolling weight of 275 pounds per inch of rolling width. B.Equipment Configuration: The cold recycling equipment will consist of a unit or a combination of units which will satisfactorily perform the following requirements: 1.Mill the bituminous pavement and pick up the RAP. 2.Process the RAP material to meet the specified gradation. The RAP material will be processed by a closed circuit system capable of continuously returning oversized material to the crusher. 3.Mix the RAP material uniformly with the specified amount of emulsified asphalt. 4.Deposit the mixture in a windrow or paver. 5.Place and compact the recycled mixture to the specified density with automatic line and grade controls. C.Equipment Performance: The milling unit will be capable of milling the asphalt concrete pavement at least 5 inches deep and a minimum of 12 feet wide in a single pass. The unit will have automatic controls capable of maintaining uniform grade and cross slope. The milling unit will have a continuous weighing system with a meter to accurately measure the amount of water being added at the milling unit. The water pump will shut off automatically if the milling unit is stopped.