Stochastic Robustness of Cable Dome Structures Under Impact Loads

Previous studies have rarely investigated stochastic robustness of flexible cable dome structures under impact loads. In this study, the dynamic responses and failure modes of a Geiger cable dome structure were analysed under impact loads. The number of components damaged by impact and the loss of internal force in components were used to establish a structural damage index and an equation of failure mode control. Following this, by establishing the impact resistance failure limit state equation and combining the probabilistic and statistical characteristics of each design parameter of the structure, the probability of disproportionate failure of the structure undergoing disproportional damage under the impact load was calculated. Then, the stochastic robustness index \({I}_{\text{rob}}\) $I_{\text{rob}}$ based on the probability of structural failure was proposed, and the key factors affecting the structural robustness were analysed through parameter analysis. The research results indicated the following. First, cable dome structures exhibited three types of failure modes under impact loads. Second, the stochastic robustness index fully reflected the probability of a cable dome structure sustaining disproportional damage under impact loads. Increasing the mass or speed of the impactor both increased the probability of the structure sustaining disproportional damage. An impact occurred closer to the centre of the structure, both the probability of overall structural failure and structural robustness performance increase, but the probability of the structure sustaining disproportional damage decreases. Third, increasing the prestress and cross-sectional area of the components might increase their impact resistance and structural robustness performance.