Earthquake-induced collapse of steel latticed shell: Energy criterion implementation and experimental validation

摘要

The collapse of steel latticed shell (SLS) under earthquake is studied in this paper. Based on the structural energy equilibrium, the properties of the energy components (kinematic, damping-dissipated, deformation-related, and input energy) are analyzed. For a stable SLS, the damping-dissipated energy and the hysteretic energy monotonically increase throughout the dynamic response process. When instability happens, the sum of these two energy components decreases. Based on this observation, a straightforward and easy-to-implement energy criterion is developed for the dynamic instability and collapse of an SLS. The criterion is validated by shaking table tests on a scaled SLS model. The span and rise of the model are 3.6 m and 0.9 m. The model is subjected to the three-dimensional El Centro earthquake record with varied severities. Visible instability (under excitation with PGA = 1.2 g) and collapse (under excitation with PGA = 1.5 g) of the model are well revealed via the energy criterion. Since the criterion is based on the global response status of the SLS, it is more comprehensive and objective than the conventional IDA-based approaches (relying on the subjectively assumed limit-states). Meanwhile, the computation of energy components involved in this proposal can be easily conducted on commercially available codes, for example, ABAQUS. This suits the demand of the engineers.