VIBRATION CHARACTERISTICS OF THE SCHOOL GYMNASIUM WITHA SINGLE LAYER LATTICE ELLIPTIC PARABOLOID SHELL ROOFSTRUCTURE SUBJECTED TO EARTHQUAKE MOTION

摘要

The purpose of this study is to investigate mechanical properties of a single layer lattice elliptic paraboloid shellrn(EP shell) structure subjected to earthquake motion and propose an estimation method of the membrane stressrnand the deformation for its earthquake-proof design. In case of using roof structures of large span buildingsrnsubjected to horizontal earthquake motion, the seismic load of the roof structure is transferred from the roof tornthe substructures. This study deals with a single layer lattice roof type EP shell structure subjected to a shearrnforce. The static and dynamic analyses have been carried out to investigate the behaviors such as the memberrnstress distribution, the deformation, the rigidity, the natural period, and so on. Based on the analyses, anrnestimation method is proposed to calculate the member stress and the displacement using several equations. Thernproposed equations are formulated using the principle of the virtual work. The calculation results of thernestimation method show good agreement with the numerical analyses using a computer. Structural engineers willrnbe able to carry out the earthquakeproof design of the EP roof type structures using the outcome of this study.