Part 1 of Sigel wall design 2007

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7. Do not operate tracked construction equipment directly on the geosynthetic reinforcement. At least 6 inches of compacted backfill soil is required prior to operation of tracked vehicles over the geosynthetic reinforcement. Keep turning of tracked construction equipment to a minimum. 8. Rubber -tired equipment may pass over the geosynthetic reinforcement at speeds of less than 5 miles per hour. Turning of rubber -tired equipment is not allowed on the geosynthetic reinforcement. 3.07 BACKFML PLACEMENT A. Place reinforced backfill, spread and compact in a manner that will min inize slack in the reinforcement. B. Place fill within the reinforced zone and compact in lifts not exceeding 6 to 8 inches (loose thickness) where hand -operated compaction equipment is used, and not exceeding 12 inches (loose thickness) where heavy, self-propelled compaction equipment is used. 1. Only lightweight hand -operated compaction equipment is allowed within 4 feet of the back of the retaining wall units. If the specified compaction cannot be achieved within 4 feet of the back of the retaining wall units, replace the reinforced soil in this zone with drainage aggregate material. Note to Specifier. In Paragraph below, select revised modified Proctor densities if necessary, in lieu of standard Proctor densities specified C. Minimum Compaction Requirements for Fill Placed in the Reinforced Zone 1. Walls Less Than 15 Feet High: Compact to 95 percent of the soil's standard Proctor maximum dry density (ASTM D698) [modified Proctor maximum dry density (ASTM D1557)] for the entire wall height 2. Walls 15 Feet High BUT NOT MORE THAN 30 Feet High: Change compaction requirements to 98 percent of the soil's standard Proctor maximum dry density (ASTM D698) [modified Proctor maximum dry density (ASTM D 1557)] for depths below 15 feet. 3. Walls Over 30 Feet High: Change compaction requirements to 100 percent of the soil's standard Proctor maximum dry density (ASTM D698) [modified Proctor maximum dry density (ASTM D 1557)] for depths below 30 feet. 4. Increase compaction requirements for retaining walls with slope heights at the back of the reinforced soil zone greater than 5 feet above the top of wail. Verify compaction requirements with Project geotechnical engineer. 5. Utility Trench Backfill: Compact utility trench backfill in or below the reinforced soil zone to 98 percent of the soil's standard Proctor maximum dry density (ASTM D698) [modified Proctor maximum dry density (ASTM D1557)], or as recommended by the Project geotechnical engineer. If the height from the utility to finish grade is higher than 30 feet, increase compaction to 100 percent of the standard Proctor density [modified Proctor density]. a. Utilities must be properly designed (by others) to withstand all forces from the retaining wall units, reinforced soil mass, and surcharge loads, if any. 6. Moisture Content: Within 2 percentage points of the optimum moisture content for all wall heights. 7. These specifications may be changed based on recommendations by the Project geotechnical engineer. a. If changes are required, the Contract Sum will be adjusted by written Change Order. D. At the end of each day's operation, slope the last level of compacted backfill away from the interior (concealed) face of the wall to direct surface water runoff away from the wall face. 1. The General Contractor is responsible for ensuring that the finished site drainage is directed away from the retaining wall system 2. In addition, the General Contractor is responsible for ensuring that surface water runoff from adjacent construction areas is not allowed to enter the retaining wall area of the construction site. E. Refer to Article 3.10 for compaction testing. 3.08 CAP UNIT INSTALLATION A. Apply adhesive to the top surface of the unit below and place the cap unit into desired position. 6.02832