中文摘要：

试验以采用喷射混凝土单层衬砌结构隧道工程为背景，对不同水胶比、粉煤灰掺量及钢纤维掺量喷射混凝土力学性能、渗透性能进行研究。结果表明，喷射混凝土具有高早龄期强度，当养护龄期大于1d时，喷射混凝土强度小于普通混凝土且差值逐渐增大。随着水胶比增大和钢纤维掺量降低，喷射混凝土强度及渗透性降低；随着粉煤灰掺量增大，喷射混凝土抗压强度先增大后减小，渗透性先减小后增大，劈裂抗拉强度持续增大。同时，对喷射混凝土碳化、冻融、硫酸盐侵蚀及氯离子侵蚀耐久性能进行研究，并与同配合比普通混凝土进行对比。而后，采用x射线衍射（XRD）、扫描电子显微镜（SEM）、热分析及压汞测孔法（MIP）对侵蚀后喷射混凝土微观结构、侵蚀产物及孔结构进行分析，研究喷射混凝土与普通混凝土耐久性能差异及机理。结果表明：喷射混凝土碳化、冻融及硫酸盐侵蚀耐久性能优于普通混凝土，但抗氯离子侵蚀性能较普通混凝土弱。钢纤维的加入使喷射混凝土耐久性能提高，但对抗氯离子侵蚀性能提升不明显。

英文摘要：

Based on single shotcrete lining structure of tunnel engineering, the mechanical and permeability performance of shotcrete with different water/binder ratios （w/b） , fly ash replacements and steel fiber replacements were studied. Results showed that the early-age strengths of shotcrete were stronger than those of normal concrete. When the curing age was more than 1 day, however, the strengths of shotcrete were poorer than those of normal concrete. Moreover, with the increase of w/b and the decrease of amount of steel fiber, the permeability and strengths of shoterete would decrease. And with the increase of fly ash replacement, the compressive strength of shotcrete may firstly increase and then decrease, the permeability may firstly decrease and then increase, while the splitting tensile strength may continuously increase. Furthermore, the durability and mechanical performance of shotcrete with erosion were studied and compared with those of normal concrete. It was found that the chloride ion concentration in shotcrete was higher than that in normal concrete. However, the carbonation, freezing and thawing, and sulphate resistance of shotcrete were better than those of normal concrete. The inclusion of steel fiber can improve the durability of shotcrete, but the chloride ion concentration in shotcrete was still higher than that in normal concrete.