710 - Waterproofing and Protective Covers
Joint waterproofing is done just before placing backfill against the joint to be waterproofed. The membrane has a tendency to sag or loosen if allowed to remain unsupported for too long, particularly in warm weather. Also, it is more likely to be damaged while exposed.
New concrete, including repair areas, must be at least seven days old before applying the prime coat. Dust must be removed from the concrete surface by brush-blasting with compressed, oil-free air. The surfaces should be examined and must be dry, clean and smooth, with all sharp protrusions removed. All materials must be as specified. The actual application is as outlined in the standard specifications where a detailed account of procedures, quantities and temperature requirements will be found.
Upon completion, the joint should be protected from damage by adjacent operations. Just before placing backfill carefully examine the material for cracks, breaks, or tears that will reduce its effectiveness. When backfilling, special care is needed to avoid damaging the material with compaction equipment. The joint waterproofing is measured in place and the dimensions entered in the field book to verify final pay quantity.