为研究混凝土在循环荷载下的变形特性，进行了2种不同应变速率下(10-5/s，10-4/s)混凝土轴向循环加卸载试验，对混凝土残余塑性应变与卸载点应变的关系及其共同点应变与卸载点应变的关系进行深入分析，并采用改进的Weibull统计模型对循环加卸载曲线的包络线进行拟合。研究结果表明混凝土在循环加卸载作用下应力应变曲线的包络线与单调荷载作用下的应力应变全曲线基本一致;改进后的Weibull统计模型能较好地拟合包络线。
Abstract
In order to study deformation behaviors of concrete under cyclic loading, we performed axial cyclic loading and unloading tests of concrete were performed at two strain rates (10-5/s and 10-4/s).Relationship between the residual plastic strain of concrete and unloading point strain were analyzed,as well as the relationship between common point strain and the unloading point strain. Envelope curves of stress-strain under cyclic loading and unloading were fitted by using improved Weibull statistical model. The results show that,envelope curves of stress-strain under cyclic loading and unloading are basically in correspondence with stress-strain curves under monotonic loading; moreover ,envelope curves can be well fitted with the improved Weibull statistical model.
关键词
混凝土 /
循环加卸载 /
变形特性 /
包络线 /
应变速率
Key words
concrete /
cyclic loading and unloading /
deformation properties /
envelope curve /
strain rate
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参考文献
[1] 邓宗才,孙成栋.钢纤维混凝土在低周反复荷载下力学性能的研究.工程力学,2001,18(3):105-110. (DENG Zong-cai, SUN Cheng-dong. Study on Properties of Steel Fiber Reinforced Concrete under Cyclic Loading. Engineering Mechanics,2001,18(3):105-110.( in Chinese))
过镇海,张秀琴. 混凝土在反复荷载作用下的应力-应变全曲线. 冶金建筑,1981,(9):14-17,13. (GUO Zhen-hai, ZHANG Xiu-qin. The Stress-strain Curves of Concrete under Repeated Loads . Metallurgy Building, 1981, (9): 14-17, 13. (in Chinese))
周洪涛.混凝土循环加卸载率效应特性研究.湖北 宜昌:三峡大学,2013.( Zhou Hong-tao. The study of Dynamic Behaviour of Concrete by Cycle Loading and Unloading . Yichang, Hubei: China Three Gorges University, 2013. (in Chinese))
过镇海,张秀琴,张达成,等.混凝土应力-应变全曲线的试验研究.建筑结构学报, 1982,3(1): 1-12.(GUO Zhen-hai, ZHANG Xiu-qin,ZHANG Da-cheng,et al. Experimental Investigation of the Complete Stress-strain Curve of Concrete . Journal of Building Structures, 1982,3(1): 1-12.(in Chinese))
王春来,徐必根,李庶林,等.单轴受压状态下钢纤维混凝土损伤本构模型研究.岩土力学,2006,27(1):151-154.(WANG Chun-lai, XU Bi-gen, LI Shu-lin, et al. Study on A Constitutive Model of Damage of SFRC under Uniaxial Compression. Rock and Soil Mechanics, 2006, 27 (1): 151-154.(in Chinese))
王乾峰.钢纤维混凝土动态损伤特性研究. 湖北 宜昌:三峡大学,2009.(WANG Qian-feng. Research on Dynamic Damage Characteristics of Steel Fiber Reinforced Concrete . Yichang, Hubei: China Three Gorges University, 2009.(in Chinese))
基金
国家自然科学基金项目(51279092);三峡大学研究生科研创新基金项目(2014CX022)
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