Preventing Falls from Elevation Caused by Joist Buckling
Goals & Objectives
The problem of falls from elevations on construction sites is very serious, taking a toll in deaths, injuries and additional costs. Current research efforts on fall prevention have investigated the demographics of fall victims, but little work has been completed that examines the contribution the mechanics of the materials within the structures have to falls.
Participant (center) walking on the I-joist in the lab
One area of construction that has not received much attention is falls from elevation on residential construction sites which use wood and wood composite materials for construction. One possible cause of these falls is due to lateral buckling from unbraced joists. Fall incidents that occur as a result to lateral buckling are entirely preventable.
The goal of this research was to explore the relationship between stresses and loads caused by construction worker behavior which causes lateral buckling of wood composite I-joists. First, observations of construction activities performed by workers on unbraced beams was made. To simulate the lateral buckling behavior in the laboratory, a large safety platform containing three unbraced I-joists 20 feet long was constructed. The safety platform includes a retractable line attached to a movable trolley, which allows a person wearing a safety harness to safety walk along the unbraced joist.
Project Approach & Activities
The safety platform was being used to help measure the physical load that a walking construction worker places on the I-joists, including moving and stable positions. The safety platform was also being used to test bracing designs to help prevent the movement of the unbraced joists.
Selected Outputs and Outcomes
The results of this research will help designers of construction materials better understand the safety concerns of construction products, and also provide methods to brace these joists to help prevent lateral buckling and allow construction workers to safely perform their jobs.
Faculty and Facility
PI: Daniel Hindman, Ph.D.; Co-I: Maury Nussbaum, Ph.D.
Wood Engineering Laboratory at Department of Sustainable Biomaterials at Virginia Tech
Funding Source
“Investigating joist buckling as a cause of falls from elevation”. NIOSH. (08/01/07-07/31/10) PI: D. Hindman, Co-I: M.A. Nussbaum. R21 OH009802.
Sector: Construction
Discipline: Slips/Trips/Falls
PI: Daniel Hindman (Virginia Tech)
Co-I: Maury Nussbaum (Virginia Tech)