考虑既有建筑最不利方向的抗震能力评估方法

主要研究在役结构的抗震性能评估方法。首先,在前人研究的基础上,给出了在役结构的力学模型;其次,通过对2次小震的动力时程分析,得出结构的最不利方向,并在此方向上利用三维分析程序CANNY 99,对结构进行Pushover分析,将得出的结构能力曲线与由实际地震波得到的需求谱叠合,求出结构性能点,进而评估结构的抗震性能。通过一算例具体说明该方法的应用步骤,并由程序输出结构在到达性能点时的梁柱破坏情况。本文从钢筋锈蚀和混凝土老化这两个方面考虑使用年限对结构的影响;同时,从结构的最不利方向对结构进行Pushover分析,考虑了结构在地震作用下柱子双向受弯的特点,更加符合实际情况。

Assessment Method for Seismic Capacity of Existing Buildings in the Most Disadvantageous Direction

This paper studies the seismic performance evaluation method of existing structures.Firstly,mechanical model of the structure in service is given based on previous studies.Secondly,the most disadvantageous direction of structure is obtained through two small earthquake time-history analyses,and the pushover analysis is carried out in this direction using three-dimensional analysis program CANNY99.Finally,the structure performance point for seismic performance assessment is gained by superimposing the structure curves onto the actual demand spectrum of seismic wave.The procedure of the proposed method is performed through a specified example.The destruction of the beams which reach performance point is simulated by program.In this paper,the impact of service life on structure is considered based on the research of steel corrosion and concrete aging.At the same time,the pushover analysis of the structure is carried out in consideration of the most disadvantageous direction.The proposed method considers the characteristics of two-way bent of the columns and is proved to be more practicable.