Section 258 — Reinforced Concrete Retaining Walls

Description

258.01This work consists of constructing reinforced concrete retaining walls.

Material

258.02Conform to the following Subsections:

Geocomposite drain

Reinforcing steel Sealants, fillers, and seals Soil and soil- aggregate materials 714.02 709.01 712.01 704.01

Construction Requirements

258.03General. Survey according to Section 152 and verify the limits of wall instal lation. Design and construct temporary works according to Section 562. Conform to Section 257 for Contractor -designed reinforced concrete retaining walls. Excavate and backfill according to Section 208.

258.04Reinforcing Steel . Submit order lists and bending diagrams according to Subsection 104.06. Provide and place reinforcing steel according to Section 554.

258.05Structural Concrete. Provide, place, finish, and cure structural concrete according to Section 552.

258.06Backfilling. Install geocomposite sheet drain system according to Subsection 605.05. Backfill the area behind the wall with structural backfill according to Subsection 208.09. Compact each lift according to Subsection 208.10, except use an approved lightweight mechanical or vibratory compactor within 36 inches of the wall. Do not place structural backfill against concrete until 80 percent of the design strength is attained.

258.07Acceptance . Material for reinforced concrete retaining walls will be evaluated under Subsections 106.02, 106.03, and 106.04. Construction of reinforced concrete retain ing walls will be evaluated under Subsections 106 .02 and 106.04. Concrete will be evaluated under Section 552. Reinforcing steel will be evaluated under Section 554. Excavation and backfill will be evaluated under Section 208. Survey will be evaluated under Section 152. Temporary works will be evaluated under Section 562.

Measurement

258.08Measure the Section 258 pay items listed in the bid schedule according to Subsection 109.02 and the following as applicable: When measuring retaining walls by the square foot, measure by the front face of wall excluding footings.

Payment

258.09The accepted quantities will be paid at the contract price per unit of measurement adjusted according to Subsection 106.05 for the Section 258 pay items listed in the bid schedule. P ayment will be full compensation for the work prescribed in this Section. See Subsection 109.05. Payment for reinforced concrete retaining wall will be made at a price determined by multiplying the contract price by the mat erial pay factor. The material pay factor is calculated as follows: PFmaterial = 1 - 0.5 (1- PF) where: PFmaterial = Material pay factor PF = Pay f actor for concrete as determined under Section 552.