钢筋混凝土构件的抗震性能评价方法及不同指标对比研究

Comparative study on seismic performance evaluation methods and different indexes of reinforced concrete components

自抗震性能化设计要求被纳入相关规范后,我国高层建筑的抗震设计已普遍采用抗震性能化设计方法,但有关大震弹塑性分析阶段的构件抗震性能一直缺乏统一的评价指标和评价依据。首先梳理了钢筋混凝土构件关于延性变形的不同评价指标,简要说明了其特点和适用性,并对各评价指标之间的关系进行了理论换算;然后采用有限元软件ABAQUS数值模拟了典型钢筋混凝土梁、柱构件在不同轴压比和不同配箍率下的单调加载试验与低周反复试验,获得了其滞回曲线和骨架曲线,并将结果与美国规范ASCE 41-17和我国《建筑结构抗震性能化设计标准》(T/CECA 20024—2022)的弦线转角评价指标及其参数进行了对比研究;最后结合结构大震弹塑性分析时的单元划分尺寸及与弦线转角指标的对应关系,提出了钢筋混凝土构件基于材料应变指标的评价参数。研究成果可为钢筋混凝土构件的抗震性能化评价提供参考。

Since the provisions of seismic performance-based design were adopted in codes,the seismic performance-based design method has been widely used in the seismic design of high-rise buildings in China.However,the evaluation indexes and evaluation parameters of structural components were still lack for seismic performance evaluation in elastoplastic analysis stage under rare earthquakes.Firstly,the different evaluation indexes of ductile deformation of reinforced concrete components were sorted out,their characteristics and applicability were briefly indicated,and the theoretical relationships between the evaluation indexes were descripted.Then,the monotonic loading tests and low-cycle repeated tests of typical reinforced concrete beams and columns under different axial compression ratios and different stirrup ratios were numerically simulated by using the finite element software ABAQUS,the hysteretic curves and skeleton curves were obtained,and these results were compared with the chord rotation index and its parameters of American code ASCE 41-17 and the Standard for performance-based seismic design of building structures(T/CECA 20024—2022)in China.Finally,the elevation parameters based on material strain of reinforced concrete components were proposed according to the meshing size of structural components in rare earthquake elastoplastic analysis and their relationships with chord rotation index.The research results can provide reference for the establishment of seismic performance evaluation of reinforced concrete components.