【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。更多还原

【Abstract】 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 correlativity between electrical potential and strain & acoustic emission(AE) rate,that is,the fracture behaviors.The electric potential 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 concrete,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.更多还原