长大隧道穿越张性富水软弱带诱发地表塌陷机理与支护荷载研究

Research on surface subsidence mechanism and supporting load of Long tunnel through a tensional water-rich weak zone

结合具体的地质参数,采用太沙基、普氏、弹塑性等传统理论进行计算,获得支护结构所需的承受荷载。在研究富水软弱带塌陷机理的基础上,考虑渗透力、真空吸蚀力、自身重力、摩擦阻力和支撑力5个因素,依据现场地质条件,按照致塌力和抗塌力两大类别构建改进的极限平衡力学模型,从而计算出支护结构所承受荷载。以后期的现场实测结果为验证标准,对上述4种方法的准确性进行校验,结果表明极限平衡力学模型是最优方法。结合具体地质条件,构建富水软弱带的极限平衡力学模型是衬砌荷载计算的新途径,对类似地质条件的隧道支护结构设计具有重要意义。

First combined with the geological parameters,traditional soil pressure theories such as like Terzaghi,Platts,and elastic-plastic were applied to reach the pressure value.Then based on the subsidence mechanism of the water-rich weak zone and geological condition,the mechanical model of limit equilibrium was created,which considered five factors,such as the seepage force,absorption and corrosion force,self gravity,friction resistance and holding force.The load condition of the lining structure can also be determined through this model.In-situ test results showed that this model provides the best estimation.Combined with the geological condition,the limit equilibrium mechanical model presents a new way for calculating the lining pressure,which provides important guidance for the tunnel lining structure design with a similar geological condition.