Experimental Investigations into Failures and Nonlinear Behaviors of Structural Membranes with Open Cuttings

Featured Application: Failure modes of structural membrane with open cuttings have been identified. The new insights can be applicable to structural health monitoring of the thin-walled shell structures.The nonlinear relationship between cutting angle and the force strongly relates to the ultimate limit state of the structural membranes.A new formula has been proposed to help engineering design and evaluate the ultimate capacity of the structural membranes with and without open cuttings.

Abstract: Reportedly, structural failures in membrane structures have occurred frequently, mostly originating from localized damage caused by intense loads on the membrane surface. It is thus necessary to investigate the nonlinear behaviors and load-carrying capacity of membranes with local damage. This study has conducted uniaxial tensile tests for membranes with a variety of original defects by using a specialized experimental setup and photogrammetry technique. The nonlinear relationship between the mechanical properties and the deforming angle of membranes, which portrays the principal axis, tensor, tensile stress, and position of the original defects, is investigated. The entire process of membrane failure has been recorded, and the strain and stress during each test specimen are compared. The new results indicate that the membranes exhibit predominantly elastic deformation before failure but surprisingly impart brittle fracture upon failure. Finally, a novel approach for estimating the load-bearing capacity of initially damaged membranes was proposed through the analysis of the load-bearing capacity of the damaged membranes under various conditions, positions, angles, and other influential factors.