Specifications Vol. II - Laserfiche WebLink

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~ - 1"'"1 . 1"'"1 . .., . .., . " . ,.., . ,., . ., . II . .., - r'I . ,.., . ..., . ..., . r"""I . II . .., . 1""'1 . Walls which do not meet these tolerances will not be accepted by the Department and must be removed and reconstructed at no cost to the Department. 548-6.4.2 Tolerances for Temporary Walls: Ensure that vertical tolerances (plumbness) and horizontal alignment tolerances do not exceed 3 inches [75 mm] when measured with a 10 foot [3.048 m] straight edge. The final overall vertical tolerance of the completed wall (plumbness from top to bottom) shall not exceed 1 inch per 3 feet [13 mm per meter] of wall height, not to exceed a total of 6 inches [150 mm]. Walls which do not meet these tolerances will not be accepted by the Department and must be removed and reconstructed at no cost to the Department. 548-6.5 Backfill Placement: Perform work in accordance with an approved Quality Control Plan (QCP) meeting the requirements of 6-8. A LOT is defined as a single lift of finished embankment not to exceed 500 feet [150 m] in length. Isolated compaction operations will be considered as separate LOTs. For multiple phase construction, a LOT will not extend beyond the limits of the phase. Place the backfill closely following the erection of each course of precast components or soil reinforcement layers and spread by moving the machinery parallel to the wall face. Do not allow equipment heavier than 8 tons [7.5 metric tons] closer than 3 feet [1 m] behind the wall face. Place backfill in a manner to avoid any damage or disturbance to the wall materials or misalignment of the facing materials. Remove and replace any wall materials which become damaged or disturbed during backfill placement at no cost to the Department, or correct as directed by the Engineer. Remove and reconstruct any misalignment or distortion of the wall facing due to placement of backfill outside the limits of this specification at no cost to the Department. Sheepfoot, grid rollers or other types of equipment employing a foot are not allowed. Achieve compaction within 3 feet [1 m] of the back of the wall face using a power operated roller or plate weighing less than 1,000 Ibs [450 kg]. At a distance greater than 3 feet [1 m] from the back of the wall, a vibratory roller may be used, provided that the frequency and amplitude combined with bulk weight of the roller has performed satisfactorily at a trial section of the same type of wall. A smooth wheel or rubber tire roller is considered adequate. Ensure that the maximum lift thickness after compaction does not exceed 6 inches [150 mm]. Decrease the lift thickness if necessary, to obtain specified density. Perform backfill compaction in a way that the compactor moves in a direction parallel to the wall face and proceeds from a distance not less than 3 feet [1 m] behind the wall face toward the end of the soil reinforcement element. Ensure that the moisture content of the backfill material prior to and during compaction is uniformly distributed throughout each layer of material. Use backfill material having a placement moisture content at the dry side of the Optimum Moisture content. To achieve the required compaction moisture content, use water that meets the requirements of Section 923. Do not use saltwater. Do not transport excessively moist backfill materials to the site for any reason. The Engineer will determine the Optimum Moisture Content in accordance with FM 5-521. At the end of each day's operation, shape the last level of backfill to permit runoff of rainwater away from the wall face or provide a positive means of controlling run off away from the wall such as temporary pipe, etc. 09/09 01000-126 03-4122.F