人工负温高强混凝土动态力学特性研究  

Study on dynamic mechanical properties of artificial negative temperature high strength concrete

作　　者：赵丁鸿 孙凤玲[2] 单仁亮[1] 宋永威 赵伟[1] ZHAO Ding-hong;SUN Feng-ling;SHAN Ren-liang;SONG Yong-wei;ZHAO Wei(School of Mechanics and Civil Engineering,China University of Mining and Technology,Beijing 100083,China;Avic Institute of Geotechnical Engineering Co.,Ltd.,Beijing 100098,China)

机构地区：[1]中国矿业大学(北京)力学与建筑工程学院,北京100083 [2]中航勘察设计研究院有限公司,北京100098

出　　处：《煤炭工程》2018年第10期56-60,共5页Coal Engineering

基　　金：国家自然科学基金资助项目(41572270);中建股份科技研发计划资助(CSCEC-2017-Z-20)

摘　　要：为研究人工负温早龄高强混凝土的动态力学特性,采用SHPB试验系统对-7℃不同龄期高强混凝土进行单轴冲击压缩实验,得到多组不同应变率作用下的动态应力应变曲线。研究发现:高强混凝土的强度具有明显的温度效应;标准及-7℃养护环境下,混凝土试块3d强度分别为单轴抗压强度的77. 4%、46. 7%;在低应变率作用下,负温混凝土脆性比较明显,中高应变率(大于30s^(-1))作用下,负温混凝土韧性增加,脆性降低;动态抗压强度、峰值应变具有明显的应变率相关性,三个龄期的峰值应变均在0. 002~0. 004;同一应变率及龄期的混凝土,其强度及弹性模量均随着受冲击次数的增加而减小,相反,其峰值应变变大。In order to study the dynamic mechanical properties of artificial negative temperature early age high strength concrete,the impact compression tests were conducted on different age of high strength concrete at-7℃ on SHPB apparatus. In the SHPB tests,a lot of stress-strain curves were gained with different strain rate. It is found that the effect of curing environment temperature on high strength concrete strength is great. Under the standard and-7℃ curing environment,the 3 d strength of concrete specimens are 77. 4% and 46. 7% of the uniaxial compressive strength respectively. At low strain rate,brittleness of negative temperature concrete is more obvious. In the medium-high strain rate（ more than 30 s^（-1））,the toughness of negative temperature concrete increases,but brittleness decreases. The dynamic compressive strength and peak strain have obvious strain rate relationship. Three age peak strains are in 0. 002 ~ 0. 004.Under the same strain rate and age of concrete,the strength and elastic modulus increase as the impact number decreases,on the contrary,the peak strain increases.

关 键 词：单轴冲击压缩 应变率 动态强度增长因子 早龄混凝土 

分 类 号：TU528[建筑科学—建筑技术科学]