Geometrically Nonlinear Analyses of Tensile Structural Systems: Wind-Structure Interaction

Abstract

Tensile structural systems as for example cables nets, suspended bridges or membranes usually have nonneglecting p-delta effects under wind action. Consequently, great displacements give a geometrically nonlinear structural behavior. In addition, the wind action is nonlinear spatially and time depending. This closely affect the dynamic interaction between loads and structure. For this reason, the calculation process needs to take into account the timedepending nonlinear response of the structure. Finally, the wind action can be critical for structural and it can induce global or local instability. Analyses has to be able to capture and to describe the instability response in term of displacements, in the case of cables net, or rotations, in the case of suspended bridges. The paper is focused on the wind-structure interaction analyses carried out by wind tunnel experiments. The wind action is generally given by wind tunnel experiments, and it is time depending. For roofs, it generally is given as pressure time histories measured by some pressure taps on the roof. The process from experiments to structural response is described using a case of study of cables net. The dynamic geometrically nonlinear analyses were performed using the TENSO non-commercial program, which can execute dynamic step-by-step integration of the nonlinear three-dimensional structure with geometric nonlinearities by the Newmark-Beta method with Rayleigh damping.