Section 608b -– asphalt concrete sidewalks 608B. 01 Description

Yüklə 16.38 Kb.
ölçüsü16.38 Kb.
Amend Section 608 - Sidewalks to read as follows:
608B.01 Description. This section describes work includes constructing asphalt concrete bituminous or concrete sidewalks. according to the contract.
608B.02 Materials. Materials shall conform to the following:

Asphalt Concrete Pavement Mix No. V 401

Bed Course Material for Sidewalks and Curbing 703.16(A)
Increase asphalt content for Asphalt Concrete Pavement Mix No. V at least 0.5 percent above that used for asphalt concrete pavements.
Joint Fillers 705.01
Reinforcing Steel 709.01
Concrete for sidewalks shall conform to Section 601   Structural Concrete and shall be Class B.
Bituminous concrete for sidewalks shall conform to Section 401   Asphalt Concrete Pavement and shall be Type V.
Concrete and bituminous mixes will be subject to inspection and tests at the mixing plants for compliance with quality requirements.
The condition of materials will be subject to inspection for acceptance before or during incorporation of materials into the work.
608B.03 Construction Requirements
(A) Excavating. Excavate to required depth and compact subgrade to firm, even surface. Replace soft and yielding material with accepted material and compact.
(B) Forms. Use full-depth wood or metal forms that are straight, free from warp and of sufficient strength to resist pressure of asphalt concrete without springing. Brace and stake forms to remain in both horizontal and vertical alignment until removal.
(C) Bed Course. Use aggregate for untreated base in accordance with Subsection 703.16(A) - Bed Course Material for Sidewalks and Curbing, as bed course material. Place bed course material a minimum of 4 inches in depth. Compact with at least three passes of lightweight mechanical tamper, roller, or vibratory system.
(D) Placing Asphalt Concrete. Place asphalt concrete on compacted base course to the required depth. Compact asphalt concrete with hand operated or power roller. Hand tamp areas inaccessible to roller. Compact asphalt to 90 percent of maximum theoretical density according to AASHTO T 209.
(E) Finishing. Finish sidewalk as plane surface with 2 percent cross slope towards roadway.
(F) Backfilling. After sidewalk has set, fill remaining excavated areas with accepted material. Place and tamp accepted material in layers up to 6 inches in depth.
(A) Concrete Sidewalks. Place concrete sidewalks four inches thick either reinforced or unreinforced as shown in the contract.
(1) Preparation. Shape and compact the foundation to a firm even surface conforming to the section shown in the contract. Remove and replace soft and yielding materials with acceptable material.
(2) Forms. Forms shall be of wood or metal and shall extend for the full depth of the concrete. Forms shall be straight, free from warp and of sufficient strength to resist the pressure of the concrete without springing. Bracing and staking of forms shall be such that the forms remain in both horizontal and vertical alignment until their removal.
(3) Placing Concrete. Moisten the foundation thoroughly immediately before placing the concrete. Place the concrete according to Section 503   Concrete Structures.
(4) Finishing. Work the surface with a wooden float and broom finished. The Engineer will not permit plastering of the surface.
Edge the outside edges of the slab and joints with a 0.25 inch radius edging tool.
The surface of the sidewalk shall be a true plane with a 0.25 to 12 slope toward the roadway.
(5) Joints. Form the construction joints around appurtenances such as manholes and utility poles extending into and through the sidewalk. Install 0.25-inch thick premolded expansion joint filler in these joints. Install 0.5-inch thick premolded expansion joint fillers between concrete sidewalks and any fixed structure such as a building or bridge. Extend the expansion joint material from the bottom of the slab to approximately 0.25 inch below the top surface of the concrete construction.
Divide the slab between expansion or construction joints into sections approximately five feet in length by transverse weakened plane joints formed by a jointing tool. Also, provide transverse weakened plane joints when the time period between consecutive concrete placements is more than 45 minutes. Form the weakened plane joints into the concrete to a depth of 0.25 of the thickness and approximately 0.125 inch in width with a scoring tool which will leave the edges round. Where slabs are more than 7 feet in width, form weakened plane joints longitudinally to obtain secure uniform blocks that are approximately square. Install weakened plane joints where the corners of drop inlets project into the sidewalk.
Match joints with the curb or pavement joints.
(6) Curing. Cure the concrete for at least 72 hours. Curing shall be by moist burlap or mats or by other accepted methods. During the curing period, exclude pedestrian and vehicular traffic. Exclude the vehicular traffic for such additional time as the Engineer may specify.
(B) Bituminous Sidewalks.
(1) Preparation and Forms. Preparation and forms shall conform to Subsections 608.03(A)(1)   Preparation and 608.03(A)(2)   Forms.
(2) Bed Course. Place the bed course material in layers not exceeding four inches in depth. Compact each layer thoroughly.
(3) Placing Bituminous Sidewalk Material. Place bituminous sidewalk material on the compacted bed course in one or more courses shown in the contract to give the required depth when rolled. Compact by a hand operated or power roller of a type and weight acceptable. In areas inaccessible to the roller, the Engineer will permit hand tamping. Compact bituminous sidewalk material uniformly.
The compaction requirement shall be 90% of the maximum theoretical density using AASHTO T 209. The Contractor shall increase the asphalt content at least 0.5% above that used for asphaltic concrete pavements.
608B.04 Method of Measurement. The Engineer will measure Asphalt concrete sidewalk will be paid on a lump sum basis.and bituminous sidewalk per square yard. Measurement for payment will not apply.
608B.05 Basis of Payment. The Engineer will pay for the accepted asphalt concrete sidewalk on a at the contract lump sum basis.unit price per square yard complete in place. Payment will be full compensation for the work prescribed in this section and the contract documents.The price includes full compensation for excavating; backfilling; installing reinforcing steel; placing and compacting bed course material; furnishing and placing the concrete; installing expansion joint material, weakened plane joint, and ramps; and furnishing labor, materials, equipment, tools, and other incidentals necessary to complete the work.
The Engineer will pay for the accepted bituminous sidewalk at the contract unit price per square yard complete in place. The price includes full compensation for excavating; backfilling and compacting the sub-surface or bed course; furnishing and placing the bituminous sidewalk and ramp; and furnishing labor, materials, equipment, tools, and other incidentals necessary to complete the work.
(If have pay item for Section 650 – Curb Ramps, delete the phrase “and ramps” above.
The Engineer will pay for the following pay item when included in the proposal schedule:make payment under:

Pay Item Pay Unit
Asphalt Concrete Sidewalk Square Yard Lump Sum”
Bituminous Sidewalk Square Yard”


(Project No.)

608B-a 11/03/04

Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur © 2016
rəhbərliyinə müraciət

    Ana səhifə