ON THE ROBUSTNESS OF CABLE SUPPORTED STRUCTURES, A THEORETICAL AND EXPERIMENTAL STUDY

摘要

While many studies have been devoted to the robustness evaluation of frame structures, little attention has been paid to the robustness-based design of cable-supported structures. Based on H_∞ control theory, the structural robustness of a structure is accessed with the H_∞ norm of the structure system transfer function. Following the SIMP approach, an artificial isotropic material model with penalization for elastic constants is assumed and relative density variables are used for describing the structural layout. A robustness-based topology optimization problem is then introduced, to search for the minimum linear robustness index, and the particle swarm optimization algorithm is used to solve this problem. Taking a cable-supported doubly-curved spherical shell as an example, the topology configuration was obtained through the robustness based design method. Finally, two experiments involving static overloading and impact loading were conducted and the robustness of the two models were analyzed and compared. It is shown that the H_∞ based robustness measure can be used to assess whether the consequences of failure are disproportionate or not and to what extent the structural behavior would be affected by changes of environmental conditions. These results provide new potential approaches to the conceptual design of cable-supported structures.