Date of Graduation


Document Type


Degree Type



Statler College of Engineering and Mineral Resources


Industrial and Managements Systems Engineering

Committee Chair

Kevin Rider


Masonry has very high incidence rate of all construction trades for injuries with lost workdays due to overexertion involving lifting in the USA. An increasingly frequent masonry task is the construction of retaining walls for landscaping purposes, whereas retaining wall blocks typically weigh 80 pounds or more, and are oddly shaped with poor hand coupling. Due to the extreme weight of the blocks and poor hand coupling, workers are often required to use awkward postures and jerking motions during the lift and place of the block. As a result of these challenges associated with manipulating these blocks by hand, tools have been designed to assist the mason during the lifting task. Unfortunately, these lifting tools have not been shown to actually reduce the risk of an injury, and even the expected benefits from their use are speculative. It is essential that the design and use of these tools are evaluated to ensure that these workers are not being placed at an increased risk of injury. The efficacy of a block lifting tool (Versa-Lok Lifter) for reducing biomechanical strain on the worker has been evaluated based on the data of joint stresses and population-based strength provided by University of Michigan's 3D Static Strength Prediction Program (3DSSPP). The study shows that the Versa-Lok Lifter can reduce the low back compression during the lifting. However using this tool may increase the risks for some major joints of human body at high levels.