Tests for dynamical progressive collapse of a grid structure based on key member failure

With a test model of a grid structure, tests were done for the progressive collapse of the structure based on member failure. The member importance evaluation method based on member axial force and strain energy change response was adopted to determine the initial failure member and a manually controlled failure apparatus was introduced. In tests, by using dynamic strain meters, guyed displacement and acceleration sensors, the time history curves of strain, displacement and acceleration of the model structure, in the dynamic process due to the initial failure were obtained. They revealed the collapse process and mechanism of the grid structure. The numerical simulation analysis and test results showed that the members between bearings and their adjacent members of the grid structure are key ones causing the progressive collapse of the grid structure after their initial failure; so, in the actual design, it is necessary to strengthen their load-bearing capacities. © 2015, Chinese Vibration Engineering Society. All right reserved.