不同偏压角度下浅埋隧道开挖施工力学行为研究

Study of the Mechanical Behavior of Shallow Buried Tunnel Excavation under Different Deflection Angles

为探究在不同地形偏压角度下由于隧道开挖而对围岩产生的力学效应,通过数值模拟建模,计算并分析了不同偏压角度对隧道施工的影响,结果表明:隧道各控制点处的最大位移绝对值小于10 mm,表明浅埋隧道开挖时,地形偏压对于隧道周边收敛值的影响存在一定的影响,但总体上影响较小。不同偏压角度的沉降变化曲线形态类似,随着偏压角度的增大,左拱腰在开挖初期有隆起的趋势,但是在开挖后期,却出现了下沉,并且下沉量也有加速增大的趋势。

In order to investigate the mechanical effect on the surrounding rock due to tunnel excavation under different topographic deflection angles,the effect of different deflection angles on the tunnel construction was calculated and analysed through numerical simulation modelling.The results show that the maximum displacement at each control point of the tunnel is less than 10 mm in absolute value,indicating that there is a certain influence of topographic deflection on the convergence value around the tunnel during shallow buried tunnel excavation,but the overall influence is small.The settlement curves for the different deflection angles have a similar pattern,with the left arch waist tending to bulge at the beginning of the excavation as the deflection angle increases,but at the end of the excavation there is subsidence and an accelerated increase in the amount of subsidence.