Research On Reinforced Concrete Structures Under Earthquake Excitation Based On Energy Method

For a long time, maximum displacement estimation of seismic structures has been adopted as the single evaluation indicator of earthquake damage, and elastic design response spectrum has been adopted to evaluate earthquake action. Basically, this design method can not reflect the impact of ground motion duration on the structural damage not can it provide a reasonable explanation for many seismic phenomena. However, from the perspective of energy dissipation, description of structural plastic accumulated damage, and description of the role of ground motion on the structure can be carried out in a simple and easy way. Besides, it can well reflect the overall impact of ground motion intensity, spectral characteristics and especially the structural damage in case of strong shock. Therefore, structural analysis and design methods of seismic energy are drawing more and more attention. The key to the research into structural response in earthquakes from the perspective of energy lies in researching into the laws of structural seismic input energy and hysteretic energy structure. And only with this research as a basis can we conduct further analysis in methods applicable for practical structure designing.The main purpose of this paper is to identify the laws governing total structural energy input and the distribution of total structural energy input under earthquake. Its main tasks are:(1) The preparation of both linear and three single degree of freedom linear model of stiffness degradation in time-history procedures; the preparation of multi-DOF linear stiffness degradation model for the three time-history program. Using two-linear and three-linear stiffness degrading models to analyze the impact of it on input energy.(2) Changes in seismic amplitude structure of the total input energy and its distribution.(3) Changes in structural damping parameters on the total input energy and its distribution coefficient.(4) Changes in dynamic parameters on the total input energy and its distribution coefficient.This study shows that seismic performance has direct relation with the structure's dynamic characteristics. Thus we should proceed from the structure to explore the dynamic characteristics of structure to evaluate its seismic performances.