Master of Science

thesisFalls and injuries related to falls are a prevalent safety concern in high fall risk sites such as hospitals and nursing homes. Injuries occurring from a fall can lead to complications, including increased length of hospital stay, increased cost, and even death. This study aims to investigate how a compliant flooring system reduces the risk of bone fractures occurring from a fall. We tested complaint floorings and proposed a new flooring design using sorbothane as an underlayment for popular vinyl sheet flooring. Experimental impact testing was performed for seven different flooring compositions consisting of Vinyl Composition Tile (VCT), Ecore Forest Rx, rubber tile, three thickness of sorbothane (0.1",0.125", 0.2") with vinyl sheet flooring on top, and lastly 0.2" thick sorbothane all at two different velocities. The two velocities chosen for the experiment were taken from literature studies that found the average impact velocities of falls with contact occurring at the hip and wrist. A finite element analysis simulation was developed in ANSYS Workbench to estimate the impact force values across a larger range of impact velocities and to identify an optimal thickness of sorbothane. Results of the experimental testing indicate that each of the complaint floorings showed statistically significant lower impact force compared to VCT. Each of the floors besides the rubber tile also had improvements in the time to peak impact force and energy absorbed up to the peak impact force. The best performing flooring for attenuation of impact force was the proposed flooring consisting of 0.2" thick sorbothane. The iv sorbothane showed no statistical significance with or without the vinyl, indicating that the vinyl did not affect the behavior of the sorbothane. The results of the FEA simulation for VCT had an error of 193.4% and 152.48% of impact force for the high and low velocity tests compared to the experimental results. For sorbothane, the simulation had an error of 120.5% and 77.9% for the high and low velocity cases from what was experimentally tested. The simulation identified that the optimal thickness of sorbothane to be used as a floor would be 0.60 inches thick