Seismic performance parameter of latticed shell based on overall stiffness reduction factor

To study the seismic performance parameters, index and limit values for the latticed shells to realize fast evaluation and check of the seismic performance, the latticed shell is simplified to the equivalent single degree of freedom(ESDOF) system by using the modal pushover analysis method based on the overall structural stiffness parameters, and the seismic responses of this structure is also analyzed. Based on the overall structural stiffness parameters and the ESDOF system, a new seismic performance parameter, overall stiffness reduction factor(OSRF), is introduced, and its accuracy is proved. The OSRFs of 0.10, 0.75, 1.00 are set as the boundary values for slight damage, moderate damage, severe damage and collapse of K6 lattice shells with the ratio of rise to span of ¼ or greater, respectively. The OSRFs of 0.10 and 0.80 are set as the design limit values at the linear-elastic and elastic-plastic stages, respectively. The analysis results of the numerical examples show that the ORSF has good applicability and can be used for fast evaluation and check for the seismic performance of latticed shells as well as structural design and optimization