Static response of a spindle-shaped tensairity column to axial compression

Tensairity is a new lightweight structural concept consisting of struts and cables stabilized by a textile membrane, which is inflated by low pressurized air. In order to estimate the potential of Tensairity beams towards applications including axial compressive loads, full-scale compression experiments were conducted on a simply-supported spindle shaped Tensairity column. The column was subjected to axial compressive loading for various levels of internal air-pressure in order to quantify its effect on local and global response, and it was found that the axial stiffness of the column increases with air-pressure and eventually reaches a plateau. Displacements were measured in several positions along the span, whereas axial forces were experimentally determined by strain gauges measurements. The experimental results were compared to finite element and analytical predictions, yielding good correlation for low air-pressure levels, whereas for higher ones, local imperfections led to significant deviations. Comparisons of the Tensairity column to similar truss-type structures with comparable stiffness revealed the superiority of the concept in terms of transportation volume and in-situ deployment.