ANALYSIS OF FRAME-CORE WALL BUILDINGS CONSIDERING EFFECTS OF AXIAL FORCE AND AXIAL DEFORMATION

Abstract

The effects of axial force and axial deformation in columns on dynamic characteristics of frame-core wall tall buildings are considered in the present study. The governing equations of motion for the structure are formulated through a continuum approach idealizing the whole structure as a shear-flexure cantilever. The frame components are replaced by continua with equivalent shear rigidity, GA, and flexural stiffness, EIa. The effect of axial force is included in the derivation of shear stiffness. Charts are presented to facilitate the determination of shear rigidity for different levels of axial force ratio, P / Pcr , in practical range. Core walls are treated as a flexural cantilever with bending and warping stiffness, EI w, and torsional rigidity, GJ. The validity and versatility of the method are illustrated through numerical examples where results from the proposed method are compared with those obtained from finite element software, ETABS.