表面处理对玄武岩纤维活性粉末混凝土力学性能的影响及断裂特性

Influence of surface treatment on basalt fiber reactive powder concrete mechanical properties and fracture characteristics

使用偶联剂KH-550和盐酸对玄武岩纤维进行表面处理,研究改性条件对玄武岩纤维活性粉末混凝土力学性能和工作性能指标的影响,并分别优选出最佳改性条件:偶联剂质量分数为0.75%,盐酸浓度为3 mol/L,刻蚀时间为60 min,刻蚀温度为20℃。采用声发射技术对比改性前、后玄武岩纤维活性粉末混凝土的损伤特征,确定试样在抗折试验中的断裂阶段和断裂模式。结果表明:声发射参数中,累计声发射(AE)命中、累计能量和振幅与玄武岩纤维活性粉末混凝土的损伤阶段有关,纤维改性对混凝土损伤的最后阶段有所影响。另外,在加载过程中,上升角(RA)和平均频率(AF)有相反的趋势,均随着断裂模式的变化而变化。

Coupling agent KH-550 and hydrochloric acid are used for basalt fiber surface treatment to investigate the effect of modification conditions on the mechanical properties and working performance indexes of basalt fiber-reactive powder concrete.The optimum modification conditions were selected as follows:0.75 wt%of coupling agent,3 mol/L of hydrochloric acid,acid etching temperature of 20℃and etching time of 60 min.By using acoustic emission(AE)technology,the damage characteristics of basalt fiber reactive powder concrete before and after modification were compared to determine the fracture stage and fracture mode of the sample in the fracture test.The results show that in AE parameters,the accumulative AE hit,accumulative energy and amplitude are related to the damage stage of basalt fiber reactive powder concrete,Fiber modification affects the final stage of concrete loading.In addition,during the loading process,the rise angle(RA)and the average frequency(AF)have opposite trends,and their changes are related to the fracture mode.