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为满足软弱围岩隧道开挖后尽快封闭岩面、适应一定变形及提供足够支护力的要求,通过素混凝土、钢筋混凝土及钢纤维混凝土衬砌力学行为室内模型试验,对钢纤维混凝土衬砌的承载特性进行研究。研究结果表明:钢纤维混凝土衬砌初裂荷载提高了20%,极限荷载得到较大提高;掺入钢纤维后衬砌结构韧性增强,初裂后仍能抵抗一定变形并较大降低变形速率,与素混凝土、钢筋混凝土相比可承受更大的变形;钢纤维混凝土衬砌初裂后承载特性曲线缓慢上升,至2倍初裂荷载时仍无收敛迹象,素混凝土快速收敛,钢筋混凝土在一定缓慢上升后快速趋于收敛,软弱围岩条件下,钢纤维混凝土初支在一定变形后可与围岩特征曲线相交,达到围岩–结构稳定状态,是一种力学性能良好的快速支护材料。研究成果对软弱围岩隧道的设计与施工都具有重要的意义。
In order to meet the requirement of closing the rock face as soon as possible after excavation of soft surrounding rock tunnel and adapting to some deformation and providing sufficient supporting force, through the indoor model test of plain concrete, reinforced concrete and steel fiber reinforced concrete lining, Characteristics of research. The results show that the initial load of the steel fiber reinforced concrete lining increases by 20% and the ultimate load increases greatly. The toughness of the lining structure increases with the incorporation of the steel fiber. After the initial cracking, the lining can still resist some deformation and greatly reduce the deformation rate. Concrete and reinforced concrete can withstand more deformation than steel reinforced concrete. The load-bearing characteristic curve of steel fiber reinforced concrete lining slowly rises after initial cracking, and shows no signs of convergence at 2 times of initial cracking load. Concrete quickly converges. After some slow rise of reinforced concrete, Quickly converge. Under the condition of weak surrounding rock, the initial branch of steel fiber reinforced concrete can meet the characteristic curve of surrounding rock after reaching a certain deformation and reach the state of surrounding rock-structure stability. It is a kind of rapid supporting material with good mechanical properties. The research results are of great significance to the design and construction of soft surrounding rock tunnels.