Nonlinear seismic analysis of flexibly connected steel buildings

摘要

This paper aims to present an efficient and robust computer method for predicting nonlinear geometric seismic response of steel buildings with flexible semi-rigid joints.A beam-to-column connection is modelled by a spring element of degradable stiffness dependent on the moment acting at.The Chen-Lui exponential mathematical function is used to fit the nonlinear curve of connection moment-rotation relationship and extended to be used in seismic analysis.A semi-rigid elastic steel frame subjected to seismic loading is studied through a numerical example.The effect of connection flexibility to the overall transient behaviour is investigated and found to be very significant and should be considered in a rigorous analysis.