不同加载速率下混凝土单轴受压性能大样本试验研究  

Large-sample experimental study on uniaxial compressive behavior of concrete under different loading rates

作　　者：李杰[1] 晏小欢[1] 任晓丹[1] 

机构地区：[1]同济大学土木工程学院,上海200092

出　　处：《建筑结构学报》2016年第8期66-75,共10页Journal of Building Structures

基　　金：国家自然科学基金重大国际合作项目(51261120374);国家自然科学基金重大研究计划项目(91315301)

摘　　要：混凝土结构在动力作用下的非线性行为受加载速率的影响较大。为了研究混凝土在动力作用下应变率效应以及这种效应对随机性的影响,进行了强度等级为C30~C60的普通混凝土棱柱体试件在8个不同应变速率(10-5/s^10-1/s)下的单轴受压应力-应变全过程大样本试验研究(共418个)。试验采用MTS815力学性能试验系统,针对每一工况,对同强度同批浇筑的约16个试件进行相同应变速率的加载。试验获得了不同强度、不同加载速率下混凝土的单轴受压应力均值-应变曲线和应力标准差-应变曲线、峰值应力和峰值应变的统计特征值。研究结果表明:加载速率对混凝土的单轴受压应力均值-应变曲线的影响最为明显,对混凝土的单轴受压应力标准差-应变曲线、峰值应力标准差、峰值应变均值和标准差的影响均不明显。The nonlinear behavior of concrete structure under dynamic loadings is strongly influenced by loading rates. To investigate the strain rate effect of concrete and its corresponding influence on the stochastic property of concrete, a total of 418 prismatic specimens with strength grade ranges from C30 to C60 subjected to uniaxial compression were tested, involving eight different strain rates between 10-S/s and 10-1/s. The experiments were conducted on the MTS815 testing system and about 16 specimens designed and casted on the same condition were tested for every set of case. The mean and standard variation values of the uniaxial compressive stress-strain curves, as well as the statistical characteristic values of compressive stress and peak strain of concrete with different strength under different strain rates, were obtained through the experiments. Experiment results indicate that the strain rate has a significant influence on the stress-strain mean value curves while other properties rarely change with strain rate.

关 键 词：混凝土 单轴受压 大样本试验 应变率效应 随机性 

分 类 号：TU528.01[建筑科学—建筑技术科学] TU317.1