钢筋混凝土柱偏心受压力学性能的细观数值研究  

MESOSCOPIC SIMULATION OF THE GLOBAL MECHANICAL PROPERTIES OF REINFORCED CONCRETE COLUMN SUBJECTED TO ECCENTRIC COMPRESSIVE LOADING

作　　者：李冬[1] 金浏[1] 杜修力[1] 卢爱贞[1] 

机构地区：[1]北京工业大学城市减灾与防灾防护教育部重点实验室,北京100124

出　　处：《工程力学》2016年第7期65-72,共8页Engineering Mechanics

基　　金：973计划项目(2011CB013600);国家自然科学基金创新研究群体项目(51421005)

摘　　要：钢筋混凝土构件的宏观力学性能由其组分—钢筋和混凝土两部分的力学性能决定。结合混凝土细观结构形式,认为混凝土是由骨料颗粒、砂浆基质及界面过渡区组成的复合材料,假定钢筋与混凝土之间完好粘结,基于钢筋混凝土柱偏心受压试验,建立了钢筋混凝土柱偏心受压加载下力学特性及破坏行为研究的细观尺度力学分析模型。通过对混凝土方形和矩形试件进行受压力学特性模拟,采用反演法确定了界面的力学参数,进而模拟了钢筋混凝土柱偏心受压加载下的宏观力学性能。结果表明,相比于宏观尺度模型,细观数值分析模型能够充分体现材料的非均质性,能够较好的模拟试件的宏观力学性能,并且能够细致的描述裂缝发展及试件破坏过程,与试验结果吻合良好。该文建立的细观尺度分析模型与方法,为钢筋混凝土构件层次宏观力学非线性及其尺寸效应研究提供了理论支持。The macroscopic mechanical properties of reinforced concrete members are determined by the mechanical properties of steel rebar and concrete. In light of the mesoscopic heterogeneity, concrete is regarded as a triphase composite material consisting of aggregate, mortar matrix and the interfacial transition zone （ITZ） at meso-scale. It is assumed that the steel rebar and concrete are well bonded. A meso-scale numerical model of reinforced concrete columns subjected to eccentric compressive loading is established. Several uniaxial compressive tests of square and rectangular concrete specimens are conducted. The mechanical parameters of the ITZs are fixed by an inversion method. The macroscopic mechanical properties of reinforced concrete column subjected to eccentric compressive loading are simulated. The simulation results indicate that the material heterogeneities can be revealed sufficiently by the established meso-scale numerical model compared with those obtained from the macro-scale model, and the macroscopic mechanical properties of the test specimen can be well simulated. The failure process of the specimens can be described elaborately. Moreover, the simulation results are consistent with the experimental observations. The meso-scale simulation method established in this study provides a theoretical support to the investigation of the size effect of reinforced concrete members.

关 键 词：钢筋混凝土柱 细观力学模型 偏心受压 尺寸效应 细观破坏 

分 类 号：TU375.3[建筑科学—结构工程]