为探究合成纤维及橡胶颗粒对湿喷混凝土力学性能的影响,在室内开展了纤维增强橡胶湿喷混凝土力学性能的测试研究,系统分析了玻璃纤维掺量、聚丙烯纤维掺量及橡胶颗粒掺量对湿喷混凝土力学性能的影响规律。结果表明:湿喷混凝土的强度指标随着玻璃纤维掺量的增加不断增大,随着聚丙烯纤维掺量的增加表现出先增大后减小的特征;玻璃纤维掺量对抗压、抗折强度的影响程度最大,橡胶颗粒掺量次之,而聚丙烯纤维掺量的影响程度最小;对于抗拉强度而言,玻璃纤维掺量的影响程度依然最大,橡胶颗粒掺量次之,聚丙烯纤维掺量最小;玻璃纤维和橡胶颗粒掺量为抗压强度的显著性影响因素,玻璃纤维和聚丙烯纤维掺量为抗拉和抗折强度的显著性影响因素;强度指标不仅受到单因素的影响,还受到因素间交互作用的显著影响;强度指标多目标优化结果表明,湿喷混凝土同时加入3种材料的最优配比为:玻璃纤维掺量0.25%、聚丙烯纤维掺量0.21%、橡胶颗粒掺量3.80%;纤维能够承担部分载荷,而添加适量橡胶颗粒能够填充试样内部孔隙,两者的共同作用增强了试样的力学性能。

To understand the influence of synthetic fiber and rubber particles on the mechanical properties of wet shotcrete,the mechanical properties of fiber reinforced rubber wet shotcrete were tested in the laboratory. The influences of glass fiber,polypropylene fiber and rubber particles on mechanical properties of wet shotcrete were systematically analyzed. The experimental findings revealed that the strength index of wet shotcrete exhibited an increase in response to an increase in glass fiber content. However,the strength index initially increased and thendecreased with an increase in polypropylene fiber content. Among the factors studied,glass fiber content had the greatest influence on compressive strength and flexural strength,followed by rubber particle content,while the impact of polypropylene fiber content was relatively minimal. In terms of tensile strength,glass fiber content remained the most influential,followed by rubber particle content,with polypropylene fiber content having the least impact. Compressive strength was significantly influenced by the content of glass fiber and rubber particles,while tensile and flexural strength were notably influenced by the content of glass fiber and polypropylene fiber. It was observed that the strength index was not solely affected by individual factors but also by the interaction between factors,which had a significant impact on the overall strength index. The results of the multi-objective optimization for the strength index indicated that the optimal ratio of the three materials added to wet shotcrete was as follows:glass fiber content of 0.25%,polypropylene fiber content of 0.21%,and rubber particles content of 3.80%. The inclusion of fibers allowed for load-bearing capacity,while the addition of suitable rubber particles effectively filled the internal pores of the samples,thereby enhancing their mechanical properties.