受压荷载下碳纤维水泥基复合材料机敏性研究

Study of Smart Behavior of Carbon Fiber Reinforced Cement-based Composites under Compression

研究了碳纤维水泥基复合材料在轴向压力下的机敏性 ,并对用于监测材料内部损伤的电阻测试法进行了探讨 .结果表明 ,这种复合材料的导电性有较显著的压力依赖性 ,在较低压力范围内电阻随压力增加而降低 ,在较高压力下随压力增大而升高 .通过对循环荷载下试件的声发射监测 ,可以认为这种电阻压力依赖性与导电网络在应力作用下的形成、重组和破坏有关 .

Smart behavior of cement based composites containing carbon fiber was studied under compression. Inner damage of the composites detected by means of electrical resistance measurement was also investigated. The results show that the conductivity of the composites is related to the pressure level. The electrical resistance decreases with increasing stress under lower pressure and increases with increasing stress under higher pressure. The breakdown and rebuild up process of conductive network under pressure may be responsible for the pressure dependence of the conductivity through detecting the specimen under cycle load by AE. The degree of damage can be monitored progressively in real time by measuring the peak Δ R / R 0.