260 Page 148PART B GRANULAR BASES AND SURFACING
260.1DESCRIPTION
This work consists of providing one or more courses of aggregate on a prepared surface.
260.2MATERIALS
A.Subbase, Base Course, Gravel Cushion, and Gravel Surfacing will conform to Section 882. Granular additives, including but not limited to, sand and rock may be necessary to produce material of the type specified. B.Clay Binder , when required for gravel surfacing, will conform to Section 883. C.Subbase, Salvaged; Base Course, Salvaged; Gravel Cushion, Salvaged; and Gravel Surfacing, Salvaged will conform to Section 884.
260.3CONSTRUCTION REQUIREMENTS
A.General Requirements: The following processing descriptions will apply to this work: Road Mix Method - Prior to placement, the Contractor will windrow and equalize the materials, including water, to the satisfaction of the Engineer. The Contractor will use a blade or other suitable equipment to spread the materials. The Contractor will windrow granular materials dumped on the prepared surface prior to incorporating additives. Central Plant Mix Method - Prior to placement, the Contractor will process and uniformly feed materials, including water, into the mixer at a predetermined rate. The plant will be equipped with positive proportioning devices and will thoroughly mix the materials. Processed granular material will be placed in accordance with the following requirements. 1.Mainline: Granular material placed on the mainline portion of the roadway will be processed by either road mix method or central plant mix method. When the material is laid by a spreader, the material will have been previously processed by the central plant mix method. The material placed will be limited to the quantity necessary to construct a maximum of a 4 inch compacted layer. 2.Shoulders: Granular material placed on the shoulder portion of the roadway will be processed and placed in accordance with the following: 260 Page 149a.Adjacent to PCC Pavement: Granular material will be processed by the central plant mix method and placed with a spreading device capable of uniformly placing the material to the specified width and depth without excessive loss of material, as approved by the Engineer. The material placed will be limited to the quantity necessary to construct a maximum of a 4 inch compacted layer. b.Adjacent to AC Pavement with Total Granular Material Thickness of 4 Inches or Less: Granular material placed adjacent to asphalt concrete pavement will be processed and placed by one of the following methods: 1)Granular material will be processed by the central plant mix method and placed with a spreading device capable of uniformly placing the material to the specified width and depth without excessive loss of material, as approved by the Engineer. The material placed will be limited to the quantity necessary to construct a maximum of a 4 inch compacted layer. 2)Granular material will be placed on the shoulder and processed by the road mixed method. The material placed will be limited to the quantity necessary to construct a maximum of a 2 inch compacted layer. c.Adjacent to AC Pavement with Total Granular Material Greater than 4 Inches: Granular material will be processed by the central plant mix method and placed with a spreading device capable of uniformly placing the material to the specified width and depth without excessive loss of material, as approved by the Engineer. The material placed will be limited to the quantity necessary to construct a maximum of a 4 inch compacted layer. When granular material is placed on the shoulder and the final finished surface is to remain granular surface next to either PCC pavement or AC pavement, the Contractor may use either of the methods described in Section 260.3 A.2.b . The granular material will be spread evenly to the specified width. Watering will be accomplished during the spreading operation. The final rolling of the top surface of the granular material will embed as many loose stones as possible. The finished surface will be smooth and free from waves and the Contractor will finish the surfacing materials to within ±0.5% of the typical section cross slope. The quarter crown within any 12 foot transverse length (or actual lane width paved with a single paver pass) will not exceed 0.04 feet when measured with a straight edge, stringline, or other suitable equipment. The centerline will be finished to a transverse distance within ± 0.25 feet of the plans shown location of centerline. Granular material used for backfilling unclassified excavation digouts, intersecting roads, and entrances will be compacted to the satisfaction of the Engineer. RCA will not be used in areas where drainage fabric, edge drains, or other similar drainage systems are present except RCA will be allowed where approach drains and transverse drains are present. 260 Page 150B.Subbase and Base Course: Each layer will be compacted to the specified density before the next lift is placed and will be rolled until a uniform and stable surface is obtained . Subbase will be compacted to 95% of the maximum dry density. Base Course will be compacted to 97% of the maximum dry density. The maximum dry density will be determined by SD 104 Method 4. The percent of the maximum dry density will be determined by SD 105, SD 110, or SD 114. C.Subbase, Salvaged and Base Course, Salvaged: Compaction and density requirements will be a minimum of 95% of the target dry density established by SD 219 and compacted under the following conditions: 1.Material will have a minimum of 4% moisture uniformly blended throughout the depth of the lift of material. The percent moisture may be adjusted by the Engineer. 2.A minimum of 1 test strip for each lift placed will be completed to determine the target dry density and optimum rolling sequence. The test strips will remain in place as part of the completed work. 3.The depth of the test strip lift will be representative of the project. 4.When there is a significant change in mix proportions, weather conditions, equipment, or other controlling factors, the Engineer may require construction of another test strip to check target density. 5.Pneumatic tired rollers will have an effective roller weight 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 face rollers will furnish a minimum rolling weight of 275 pounds per inch of rolling width. D.Gravel Cushion and Gravel Cushion, Salvaged: Compaction to a specified density is not required. Rolling will proceed simultaneously with the spreading and watering and continue in overlapping strips until a uniform, stable surface is obtained. Pneumatic tired rollers will have an effective roller weight 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 face rollers will furnish a minimum rolling weight of 275 pounds per inch of rolling width. 260 Page 151E.Gravel Surfacing and Gravel Surfacing, Salvaged: Compaction to a specified density is not required. Rolling will proceed simultaneously with the spreading and watering and continue in overlapping strips until a uniform, stable surface is obtained. Pneumatic tired rollers will have an effective roller weight 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 face rollers will furnish a minimum rolling weight of 275 pounds per inch of rolling width.
260.4METHOD OF MEASUREMENT
Subbase; Subbase, Salvaged; Base Course; Base Course, Salvaged; Gravel Cushion; Gravel Cushion, Salvaged; Gravel Surfacing (including clay binder); and Gravel Surfacing, Salvaged will be measured to the nearest 0.1 ton. The Contractor will replace material lost or wasted during the processing operation at no additional expense to the Department. Material placed in excess of the quantity needed to construct the typical section will be deducted from the final measured quantity. Water added during crushing and water mixed with granular material by a central plant will not be measured and the weight will not be subtracted from the granular material. Water for granular material, added during laydown operations, and materials which are paid for under separate items will not be measured under these items.
260.5BASIS OF PAYMENT
Subbase; Subbase, Salvaged; Base Course; Base Course, Salvaged; Gravel Cushion; Gravel Cushion, Salvaged; Gravel Surfacing (including clay binder); and Gravel Surfacing, Salvaged will be paid for at the contract unit price per ton. Payment will be full compensation for furnishing and placing materials, water added in a central plant, labor, equipment, test strips (if required), and all incidentals required. If roadway shaping is required, and a bid item is not provided, payment for the granular material items will be full compensation for necessary shaping work. 270 Page 152270 SALVAGING, PROCESSING, AND STOCKPILING GRANULAR BASE AND ASPHALT CONCRETE MIX MATERIAL
270.1DESCRIPTION
This work consists of salvaging, processing, blending, crushing, and stockpiling salvaged material from the existing roadway. Salvaged material will consist of granular material, asphalt concrete mix material, or asphalt mix and granular base material.
270.2MATERIALS
Salvaged material will meet the requirements of Section 884.
270.3CONSTRUCTION REQUIREMENTS
A.General: The Contractor will not dispose of salvaged material or use the salvaged material for any purpose other than purposes designated in the plans without approval by the Engineer. B.Salvage and Stockpile Granular Material or Salvage and Stockpile Asphalt mix and Granular Base Material: 1.Salvaging: The salvaged material will be removed and loaded in a manner that minimizes waste and avoids contamination of the salvage material with underlying subgrade soil. Scrapers will not be used for the removing or loading operations but may be used to haul the material. Salvaging of material will not exceed 2 miles in advance of the grading operation. Salvaging of material may extend to 3 miles in advance of the grading operation if approved by the Engineer. The Engineer will only approve the request if the Contractor can demonstrate that the additional distance is necessary for the grading operation and that sufficient access is provided at intersecting roads and driveways. The material will be moved toward the center of the road, to the extent necessary to ensure that salvage material is not lost down inslopes. 2.Processing: Processing and blending may be accomplished in place, provided the Contractor's method meets the blending and gradation requirements and has positive depth control. 3.Stockpiling: Asphalt concrete mix and granular material will be processed or crushed and stockpiled together so that a uniform blend is obtained. The salvaged material may be stockpiled at contractor provided sites. Prior to stockpiling, the stockpile site will be prepared by removal of the top 6 inches of topsoil and the area bladed smooth. C.Salvage and Stockpile Asphalt Mix Material: 1.Salvaging: The salvaged material will be removed and loaded in a manner that minimizes waste and avoids contamination of the salvage material. Scrapers will not be used for the removing or loading operations but may be used to haul the material. Salvaging of material will not exceed 2 miles in advance of the grading operation, unless otherwise directed. The material will be moved toward the center of the road, to the extent necessary to ensure that salvage material is not lost down inslopes.