Torsional Design Method of Bottom Frame Structure with Irregular Plane

Abstract

For the study of irregular plane adverse impacts on the bottom frame structure seismic performance, in this paper, a serious damaged bottom frame structure in Wenchuan earthquake is taken as the research object,and a comparative calculation model is designed and elasto-plastic time-history analysis is carried out on the use of ABAQUS finite element software. The calculation results show that: the stiffness center of floor with irregular plane does not coincide with the center of mass, this eccentricity will produce torsional response under horizontal earthquake action. Bottom frame shear layer has strong stiffness at the center, around the lack of lateral load resisting member will cause interlayer torsional rigidity insufficient, further increasing the torsional response of structures, aggravated the damage. The lateral stiffness ratio under the same conditions,the design method of the contrast model is more reasonable, and has lighter damage under the the same intensity grade, improve the seismic capability of the structure, and provides the ideas of design method of this kind of structure.