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摘要: 分析了采用中隔壁法施工时隧道中隔壁的变形特性, 研究了中隔壁变形和水平荷载之间的内在关系, 提出了一种新的隧道水平围岩压力计算方法。采用结构力学分析理论, 建立了中隔壁变形和水平围岩压力之间的关系, 利用中隔壁变形监测数据, 得到水平围岩压力。基于天恒山土质浅埋隧道Ⅴ级围岩, 采用谢家烋法计算的水平围岩压力为88~145 kPa, 采用新算法计算的水平围岩压力为110 kPa。其中, 当围岩摩擦角为45°时, 采用谢家烋法计算的水平围岩压力为115 kPa, 与采用新算法计算的水平围岩压力接近, 两者相差5 kPa, 验证了新算法的可行性。Abstract: The deformation feature of middle wall for tunnel during construction was analyzed, the inner relationship between the deformation and the horizontal load was studied, and a new calculation method of horizontal surrounding rock pressure for tunnel was proposed.In the method, the analysis theory of structural mechanics was adopted to establish the relationship, in which the pressure was obtained by utilizing the monitoring deformations of middle wall.The pressure of V grade surrounding rock of shallow-buried soil tunnel in Tianhengshan is 110 kPa gained by the new method, and its range is 88-145 kPa gained by the Xie Jia-xiao method.When the friction angle of surrounding rock is 45° taken by the Xie Jia-xiao method, the pressure is 115 kPa and is close to the value computed by the new method, and their difference is 5 kPa, which proves that the new method is feasible.
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Table 1. Calculation results of horizontal surrounding rock pressure
φg/(°) 40 45 50 Pressure/kPa Xie Jia-xiao method 145 115 88 New method 110 -
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