支护结构内力测试在确定隧道容许位移量上的应用探讨

Discussion on Application of Internal Force of Reinforcement Structure in Determination of Allowable Displacement of Tunnels

容许极限位移量的确定国内外尚无统一的标准,通过分析支护结构压力、内力及支护结构变形三者之间的内在联系,得出结构稳定性的判断的根本的指标应基于承载能力(支护压力)或内在的承受能力,并通过实例,利用隧道实测监测资料,建立支护结构内力-安全系数-位移这三者之间的关系,从而得出隧道的允许位移量,这一允许位移量的确定方法,对于大跨度、特殊地质条件下的隧道允许位移量的制定,尤其具参考价值。

There is no unified standard for the determination of the allowable ultimate displacement both at home and abroad.By analyzing the internal relationship among the pressure,internal force and deformation of the reinforcement structure,the author draws the conclusion that the structural stability depends on the load bearing capacity.Taking Taihangshan tunnel as an example,the author establishes the relationship among the internal force,safety coefficient and displacement of the reinforcement structure on basis of the monitoring data and obtains the allowable displacement of the tunnel. The method to determine the allowable displacement presented in the paper can provide reference for the determination of the allowable displacement of large-spanned tunnels in special geological conditions.