Rev. 3-27-97
MECHANICALLY STABILIZED EARTH RETAINING WALLS
731-R-202
The Standard Specifications are revised as follows:
SECTION 105, AFTER LINE 48, INSERT AS FOLLOWS:
SECTION 731, BEGIN LINE 1, INSERT AS FOLLOWS:
SECTION 731 - MECHANICALLY STABILIZED EARTH RETAINING WALLS
(a) The design drawings shall include all details, dimensions, quantities and cross-sections necessary to construct the wall and shall include but shall not be limited to the following:
1. A plan and elevation sheet or sheets for each wall
2. An elevation view of the wall which shall include the elevation at the top of the wall at all horizontal and vertical break points at least every 15 m (50 ft) along the face of the wall, all steps in the leveling pads, the designation as to the type of panel, the length of soil reinforcing systems, the distance along the face of the wall to where changes in length of the soil reinforcing systems occur, and an indication of the original and final ground lines and maximum bearing pressures
3. A plan view of the wall that indicates the offsets from the construction centerline to the face of the wall at all changes in horizontal alignment. A plan view and elevation view which detail the placing position and connection of all steel ground reinforcing elements in areas where piling, utility, or other structures are near the wall.
4. A typical cross section or cross sections showing elevation relationship between ground conditions and proposed grades
5. All general notes required for constructing the wall
6. All horizontal and vertical curve data affecting the wall
7. A listing of the summary of quantities on the elevation sheet for each wall
(b) All panel details shall show all dimensions necessary to construct the element, all reinforcing steel in the element, and the location of soil reinforcing system devices embedded in the panels.
(c) Clearly indicated details for construction of walls around drainage facilities.
(d) All details of the architectural treatment.
(e) The details for diverting strips or mesh around obstructions such as piles, catch basins, and other utilities shall be submitted for approval.
(f) The details for each connection between the concrete panel and the mesh or strip.
MATERIALS
Materials shall be in accordance with the following:
Coarse Aggregate, Size No. 23 . . . . . . . . . . . . . . . . . .904.01
Concrete Admixtures. . . . . . . . . . . . . . . . . . .. . . . . . ..912.03
FineAggregate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 904.01
Fine Aggregate, Class A, Size No. 91 or 8 . . . . . . . . . 904.03
Fly Ash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .901.02
Portland Cement . . . . . . . . . . . . . . . . . . . . . . . . . . . . .901.01(b)
Reinforcing Steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . .910.01
Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 913.01
a. Defects which indicate imperfect molding
b. Defects which indicate honeycombed or open texture concrete
c. Defects in the physical characteristics of the concrete, such as broken or chipped concrete, or color variations or dunnage marks on the front face due to excessive form oil or other reasons.
The Engineer will determine whether spalled, honeycombed, chipped, or otherwise defective concrete shall be repaired or be cause for rejection. Repair of concrete, if permitted, shall be done in a satisfactory manner. Repair to concrete surfaces which are to be exposed to view after completion of construction shall be subject to approval.
CONSTRUCTION REQUIREMENTS
Payment will be made under:
Pay Item . . . . . . . . . . . . . . . . . . Metric Pay Unit Symbol (English Pay Unit Symbol)
B Borrow for Structure Backfil. . . . . . . . . . . . . . . . . . . . . . m3 (CYS)
Panels, Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . m2 (SFT)
Pad, Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . m (LFT)
Erection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . m2 (SFT)