Inspection Detail

Inspection: 308366657 - D & C Masonry, Inc.

Inspection Information - Office: Nc Department Of Labor - Charlotte

Investigation Summary

At approximately 9:30 a.m. on November 25, 2004, employees of D & C Masonry, Inc., were building masonry walls for a retail store. Five employees were working from two separate scaffolds. A mason, and Employee #1, a laborer, were working from the scaffold located at the east side of the building with the other employees were located throughout the remainder of the job site. The mason had just left the scaffold when the wind began gusting. According to employees on the site, the winds were moderate in the morning and increased as the morning progressed. As the wind picked up, the eastern masonry wall collapsed, knocking over the scaffolding upon which Employee #1 was working. Employee #1 was admitted to the hospital for treatment of a fractured arm and leg. At the time of the accident, the masonry wall was approximately 20 feet high and the scaffold platform was approximately 17 feet high, 50 feet wide and being built to 25 feet high. During interviews and site inspection, it was determined that no one had been designated to monitor the wind speed on the jobsite. The masonry block used was 16 in. by 8 in. by 8 in., and that Number 5 rebar was installed at 3 ft on center. The wall that collapsed was being constructed as high lift grouting, grouting poured after wall completion, but all the other walls were being grouted every 4-6 feet in height. Pipe braces were installed at height of approximately 16 feet on all masonry walls for bracing until wall was tied into the steel supporting structure. The employer stated that no concrete grouting from the supplier was available for delivery when the wall was being built so a high lift grout construction method was conducted. Concord Emergency Management Director stated that wind gusts of 35 mph were reported for the area during the time of the wall collapse. The mason and Employee #1 stated that the wind was gusting hard in the direction of the wall collapse, and that pole braces were installed on the wall that collapsed. The braces used at the site were the Dayton/Richmond T-14 Tilt-up Wall Braces type B-4 Pipe Brace. Dayton/Richmond specifies that only the T-4 anchor or the T-13 anchor be used when attaching braces to the floor slab. The T-4 and T-13 anchors are .75 inch diameter. The anchor bolts used to secure the braces to the floor slab were .5 inch diameter. The .5 inch nut and single washer were not of substantial size and strength to secure the base of the brace under the wind load.

Keywords: FRACTURE, HIGH WIND, WALL, COLLAPSE, BLOCKS, FALL, ARM, BRACING, LEG, SCAFFOLD