Component Level Testing of a Large Area Maintenance Shelter

Abstract

Large Area Maintenance Shelters (LAMS) are used by the United States military as temporary shelters for equipment and maintenance. After several LAMS structurally failed in wind speeds within the design parameters, the Air Force Civil Engineer Center (AFCEC) partnered with the Auburn University Civil and Environmental Engineering Department to determine the potential failure causes. This thesis investigates four structural components of the LAMS and describes the testing and key results from each within the context of the LAMS wind performance. Coupon tests were performed to obtain the true material properties of the LAMS components. Tension tests were performed on vinyl coated steel cables, which are the tension members in the LAMS, to obtain the material properties of the cables. The purlins are the compression members between the ribs of the LAMS. Both the compression and flexural strength of the purlins were tested for this report. Each of these items is a crucial component to the structural load path and successful wind performance of the LAMS. The research finds that overall, individual components performed as expected based on established theory and typical design values for the materials used and exhibited ductile responses. However, slip connections present in the purlin connections add significant flexibility to the lateral load path that may introduce detrimental effects, including enhancing weak axis flexural stresses in the rigid frames and enhanced fatigue effects in the purlin end connection.