修补和加固的在役混凝土结构需要有效的手段来监测和评定其安全状况。研究了连续碳纤维增强水泥基复合材料三点弯曲梁在不同加载方式下,其电阻与变形之间的变化规律,探究连续碳纤维增强水泥基复合材料的传感特性。结果表明,连续碳纤维增强水泥基复合材料试样的应变-电阻敏感度高于电阻应变片,线性度、滞后性较好,蠕变小,稳定性较好。据此,可将连续碳纤维增强水泥基复合材料用来制作感知结构损伤的传感器,实现对大型土木结构的在线健康监测。如果将其用作修补材料,那么在修补加固破损结构的同时,还可利用其应变-电阻敏感性长期在线动态监测结构的损伤及修补质量。
The patched and reinforced existing concrete structure requires efficient means to monitor and assess its safe condition.In this paper,the variation law between resistance and distortion of continuous carbon fiber reinforced cement-base composite three-point-bending beam has been researched in different loading modes;the sensing characteristics of continuous carbon fiber reinforced cement-base composite have also been probed into.The results show that the strain-resistance sensitivity of the samples of continuous carbon fiber reinforced cement-base composite is higher than the electric resistance strain gauge;their linearity and hysteresis are better;their creep age is small and their stability is better.Thereafter,continuous carbon fiber reinforced cement-base composite can be used to make sensors with damaged sensory structure,so as to achieve the online health monitoring of the large-scale civil structures.If continuous carbon fiber reinforced cement-base composite is used as patching material,while it is used to patch and reinforce the damaged structures,its strain-resistance sensitivity can also be made full use of to monitor online the damage of the structures and their patching quality long-termly and dynamically.