Study On Vertical Pushover Analysis Method Of Long-Span Spatial Structures

Pushover Analysis is a nonlinear static analysis method for anti-seismic design of structures. As an important tool of performance-based anti-seismic design, Pushover Analysis has been widely recognized and adopted in the design of high-rise buildings. However, research on Pushover Analysis of long-span spatial structures is quite less. In this paper, Pushover analysis is applied in the design of long-span spatial structures under vertical strong earthquakes. Through the comparison with nonlinear time history analysis, the feasibility of Pushover Analysis is verified.Modal Pushover Analysis is an improved Pushover Analysis method. Based on the theory of structural dynamics, Modal Pushover analysis (MPA) not only retains the conceptual simplicity and computational attractiveness of traditional procedures, but also considers the higher modes effect on the seismic behavior of the structures.In this paper, the long-span double-layer reticulated dome used in Beijing Laoshan Cycling Gymnasium is taken as a case study. With the ground motion of Elcentro, Taft and Tianjin earthquakes as input, the structural behavior under strong vertical earthquakes are studied by using capacity spectrum procedure and MPA method. The agreement of the resulted apex displacement and distribution of plastic hinges with nonlinear time history analysis proves the accuracy of the Pushover Analysis methods.Most long-span spatial structures are composed of slender members subjected to either tension or compression forces. The buckling of compression members may affect the anti-seismic capacity of long-span structures. By using Pushover Analysis Method, the effect of member buckling on the seismic performance of long-span spatial structures is studied in this paper.