Inspection Detail

Inspection: 315276014 - Iowa Bridge & Culvert, Inc.

Inspection Information - Office: Iowa 0751910

Investigation Summary

On January 24, 2011, Employees #1, 2, 3, and 4 were working inside of an approximately 24 x 36 ft PZ27 sheet piling/I-beam wale type of shoring system. Manufactured sand was being used to backfill the excavated area around a concrete pump vault that had been constructed inside the shoring. A two-tier wale system had been installed inside the perimeter of the shoring walls with the lower tier being W27x102 I-beams, while the upper tier consisted of W21x55 I-beams. Numerous approximately 6 ft long steel vertical members had been bolted up between the two wale levels. The wale system was suspended in place in the four corners via wire rope fed through holes in the sheet piles, looped under the top wale and tied back to itself. The wire rope loops were constructed with .815 in. 6x25 EIP IW RREG wire rope utilizing a parallel lap splice. Only two wire rope clips were in place at each splice, one for each dead end. As part of the backfilling/shoring removal operations, the lower section of wales and vertical members had been dismantled with the vertical members and three of the four lower wales having been removed from the area. The lower east wale was unable to be removed from the shored area due to space constraints and had been chained up to the upper wale. At the time of the accident, Employee #1 was operating a vibratory compactor, while working under the east double wales. Employee #2 was working under the north wale. Employee #3 was standing on top of the pump vault directing Employee #4 who was operating a LinkBelt 3400 backhoe, sprinkling the manufactured sand in a gap between the east wales and the nearby vault. The lap splice in the northeast wire rope loop assembly failed, dropping the north and east portion of the wale system onto Employees #1 and #2. The remainder of the wales remained elevated. Pertaining to the wire rope clips on the three remaining job-made wire rope loops, each splice was noted to have one saddle of the clip on one dead end of the rope and one u-bolt portion on the other dead end of the ropes. Employee #2 was struck in the head by the dropping north wale and was knocked to the ground. Employee #2 was not hospitalized. Employee #1 was struck by and pinned under the east wales with fatal injuries. The east double wales, including the manufactured sand placed on them, were estimated to weigh approximately 9,300 lbs. The north wale weighed approximately 1300 lbs. Employee #1 died at the scene, and his death was confirmed by the Johnson County Coroner.

Keywords: EXCAVATION, SAND, WIRE ROPE, PINNED, CONSTRUCTION, CRUSHED, STRUCK BY, BACKHOE