【摘要】 研究了在0.3%、0.5%、1.0%以及2.0%不同程度预加拉伸应变破坏下,两种不同配比、不同龄期的高延展性纤维增强水泥基复合材料M45-ECC及HFA-ECC的残余应变、裂缝分布特性、干湿自愈合循环环境中共振频率的恢复情况以及自愈合产物的微观特性。结果表明:ECC试件的残余应变约等于预加应变的50%左右;90d龄期试件拥有更多及更小宽度的裂缝;干湿循环有利于ECC材料的自愈合,大部分共振频率值的恢复都发生在4～5个循环之前;HFA-ECC的共振频率恢复值略高于M45-ECC;自愈合产物包括"纤维状"的水化硅酸钙凝胶及"颗粒状"的CaCO₃。更多还原

【Abstract】 The self-healing behavior of engineered cementitious composites（ECC） materials was investigated.The residual strain, crack distribution characteristics,resonant frequency（RF） recovery under wet/dry conditioning cycles and the micro-performance of self-healing products like M45-ECC and HFA-ECC at various pre-loadings of 0.3%,0.5%,1.0%,and 2.0%were analyzed.The results show that the residual strain is 50%of pre-loading strain.The sample aged for 90 d has a higher number of cracks,and a lower average crack width.Wet/dry conditioning cycles can favor the self-healing of the ECC materials.The most of the RF can be recovered before 4-5 cycles.The RF recovery of HFA-ECC is a bit higher than that of M45-ECC.The self-healing products are mainly C-S-H fibers and CaCO₃ particles.更多还原