混凝土断裂表面带电异常研究  

Research on surface electric anomaly of concrete in fracture

作　　者：李忠辉[1,2] 王恩元[1,2] 何学秋[1,2] 

机构地区：[1]中国矿业大学安全工程学院,江苏徐州221116 [2]中国矿业大学煤炭资源与安全开采国家重点实验室,江苏徐州221008

出　　处：《煤炭学报》2010年第6期910-914,共5页Journal of China Coal Society

基　　金：国家自然科学青年科学基金资助项目(40904028);国家自然科学基金资助项目(40874070);国家重点基础研究发展计划(973)资助项目(2005CB221505);"十一五"国家科技支撑计划(2007BAK29B01);教育部新世纪优秀人才支持计划(NCET-06-0477);中国矿业大学青年教师"启航计划"项目;中国矿业大学青年科研基金资助项目(2007A002)

摘　　要：实验研究了混凝土试件断裂破坏过程的电位信号。结果表明,混凝土在破裂过程中有电位异常产生,电位信号与试件受载的应变及其声发射率(破裂行为)具有良好的对应性。在混凝土破裂过程中,电位信号呈连续增大趋势,在主破坏时声发射率和电位信号均有大幅度增加。电位信号与试件破裂过程密切相关,可以为破裂提供前兆信息。混凝土破坏是裂纹的扩展、联合、贯通的结果,电位的主导产生机制是裂纹扩展尖端电荷分离及压电效应。The electric potential signal was experimentally studied during fracture of concrete sample. The results show that there is electric potential abnormal generated in the fracture of concrete under load, and there is a good correlativi- ty between electrical potential and strain ＆ acoustic emission （AE） rate, that is, the fracture behaviors. The electric po- tential signal shows a continuously increasing trend in the fracture process of concrete, and there is large increasing in AE rate and electric potential in the main fracture. Electric potential signal is closely related to the fracture of con- crete, which can provide precursory information for it. The fracture is synthetical results of extending ,joining and transfixion of cracks in concrete, the dominant mechanism of electric potential is charge separation at crack tip in crack propagation and piezoelectric effect.

关 键 词：混凝土 断裂 电位异常 

分 类 号：TU528[建筑科学—建筑技术科学]