偶联剂改性玄武岩纤维增强水泥基复合材料力学性能

Mechanic Properties of Cement Matrix Composites Reinforced with Basalt Fiber Modified with Silane Coupling Agent

为改善玄武岩纤维(BF)与水泥基材料的界面结合作用,分别采用质量分数为0.4%、0.8%和1.2%的γ-氨丙基三乙氧基硅烷(CG550)、γ-甲基丙烯酰氧丙基三甲氧基硅烷(CG570)和乙烯基三乙氧基硅烷(Z6518)的三种硅烷偶联剂对玄武岩纤维进行表面处理,研究改性后纤维及其增强混凝土的力学性能影响规律。实验结果表明,随着CG550溶液浓度增加,改性玄武岩纤维及其水泥基复合材料力学性能整体呈上升趋势,当CG550溶液浓度为1.2%时,纤维及其增强水泥基材料有最佳的力学性能;随着CG570溶液浓度增加,改性后玄武岩纤维的断裂强度先升高后降低,断裂伸长率基本不变,纤维断裂强度最高提升5.8%,其水泥基复合材料的力学性能随溶液浓度增加呈上升趋势,抗折强度最高提升24.4%,抗压强度最高提升7.3%;随着Z6518溶液浓度上升,改性后玄武岩纤维的断裂强度逐渐降低,但断裂伸长率逐渐增高,表现出较好的延性;其水泥基复合材料力学性能随浓度变化无明显改善。综合考虑实验结果,三种硅烷偶联剂对纤维的改性效果好坏依次为CG570、CG550、Z6518。

For improving the interface bonding effect of the basalt fiber(BF)to cement-based material,the BF was treated with different concentration(0.4%,0.8%and 1.2%)of CG550,CG570,Z6518 respectively.The mechanical properties of the treated fiber and BF enhanced cement composites are studied.The experimental results show that with the increasing concentration of CG550 solution,the mechanical properties of treated fiber and BF/cement composite increase as a whole.The treated BF and BF/cement composites have the best mechanical properties,as the concentration of CG550 solution is 1.2%.With the increasing concentration of CG570 solution,the fracture strength of treated BF increases firstly and then decreases,and the fracture elongation remains basically unchanged.The fracture strength of BF raises by 5.8%.The mechanical properties of BF/cement composites increases with the increasing of solution concentration.The highest flexural strength raises by 24.4%,the highest compressive strength raises by 7.3%;with the increasing concentration of Z6518 solution,the fracture strength of treated BF decreases gradually,but the fracture elongation increases gradually,showing good ductility.The mechanical properties of BF/cement composites is not improved significantly with the change of concentration.Considering the experimental results,the modification effects of three silane coupling agents on the fibers were ranked as CG570,CG550 and Z6518.