Frame Structure Seismic Design Based On Damage Under Near-field Earthquake Research

In recent years, great social losses, economic losses and heavy casualties have been caused by frequently strong earthquake and other serious secondary disaster. Take certain anti-seismic measures, deformation and destruction under earthquake effect could be better control, and then personnel lives and properties can be ensure. Previous research has shown that greater speed and displacement impact of building structure have been result in long-period character of near-field earthquake, so effective seismic design method under seismic action of near-field is crucial. On the basis of predecessors research findings about basic characteristics of near-field earthquake and damage performance-based seismic design method, this paper study is conducted in four following major parts.1) The definition, basic characteristics and time history function curve of near-field earthquake are introduced. Base on the principle of seismic record of time history analysis and the feature of near-field, the typical records of near-field from PEER strong motion dates are selected.2) The concept of performance-based seismic design method(PBSD), and the main kinds of PBSD methods are reviewed. Damage performance-based seismic design, which considers both displacement transcendence and energy dissipation under earthquake action, is especially focused on. The main contents of damage performance-based seismic design include its principle, definition and numerical area of damage index, damage model and so on.3) Elastic-plastic analysis method of earthquake action has been discussed. SAP2000software has been used to elastic-plastic calculate, which is one of structural finite element analysis software. Member model is used structural vibration model. Typical near-field motion and general cosco seismic motions have been input to contrastively analyze of nonlinear time history. The records show that dynamic response of structure under near-field motion is far greater than that under general cosco motion.4) The traditional damage performance-based seismic design method has been reviewed. According to predecessor research, direct damage performance-based seismic design of reinforced concrete frame structure under near-field motions has been deduced. Damage index as design control variable is introduced in initial design stage. Multiple degree of freedom system has been transformed single degree of freedom system to count. According to relationship of damage index and equivalent ductility coefficient, strength reduction factor of near-field earthquake motions, horizontal earthquake effect has been transformed base shear, then inter-laminar shear are distributed, other internal force and inter-laminar shear are combined to calculate reinforcement quantity. The design finished as above completed. Then a numerical example has been given to illustrate the feasibility of direct damage performance-based seismic design.