侧压力系数对高地应力隧道二次衬砌承载力的影响

Influence of lateral pressure coefficient on bearing capacity of secondary lining of tunnel in high ground-stress area

高地应力区隧道的地应力和侧压力系数往往沿线有所变化。为了研究高地应力条件下,侧压力系数对隧道二次衬砌承载力的影响规律,首先分析了隧道试验段的实测地应力和接触应力,确定了隧道所处的地应力及侧压力系数的大小。然后利用有限元软件ANSYS,采用荷载结构模型计算了在0.25~4.00不同侧压力系数下隧道二次衬砌的内力。最后根据内力值计算出安全系数,从而推断其极限承载能力,并总结了侧压力系数对隧道二次衬砌极限承载能力的影响规律。

The ground stress level and lateral pressure coefficients of high ground stress area of ten vary along the tunnel.In order to study the influence of lateral pressure coefficient on the bearing capacity of the secondary tunnel lining under high ground stress conditions,the measured stresses and contact stress in the tunnel test section are firstly analyzed,and the ground stress level and the lateral pressure coefficient are determined. By using finite element software ANSYS and load structure model,this paper calculated the internal force of tunnel secondary lining under different lateral pressure coefficient which is from 0. 25 to 4. 00,and concluded influence of lateral pressure coefficient on ultimate bearing capacity of tunnel secondary lining according to the safety coefficient and its ultimate bearing capacity deduced by the internal force value.