Effect of Steel Fiber Volume Ratio on Bending Moment Transfer Coefficient of SFRC Shield Tunnel Under Staggered Assembling

The transfer coefficient of bending moment is one of the key parameters of shield tunnel design. It is an important index to measure the force transfer property of shield tunnel under staggered assembling. In this paper, the mechanical parameters of segments with different steel fiber volume ratios are determined by a series of standard tests. The stiffness of joint of the SFRC shield tunnel is analyzed by numerical calculation. Based on the results, the model of the three-ring SFRC shield tunnel is established. Finally, the effect of steel fiber volume ratio on bending moment transfer coefficient of SFRC shield tunnel under staggered assembling is investigated. The result shows that the steel fiber volume ratio of segment is inversely proportional to the bending moment transfer coefficient. When the steel fiber ratios increase, the bending moment transfer coefficient at the position of 101.25° and 168.75° reduces greatly. The location of the maximum moment coefficient is not affected by steel fiber ratio increase, while the location of the minimum bending moment coefficient will shift from the roof to bottom of tunnel.