以一新建隧道为例,采用数值计算对其进行二维平面应力的有限元分析,检算在仰拱抬升不同程度后,衬砌结构的内力变化及安全系数,以供衬砌结构稳定性评估参考.结果表明:仰拱抬升程度越大,对衬砌结构弯矩、轴力、变形值影响越大,尤其是对衬砌拱脚处的弯矩值影响最为明显.实际施工中遇到类似问题需要加以重视.
Based on a newly-built tunnel,finite element numerical analysis is performed to obtain two dimensional plane stress and the safety factors and internal force changes of the linging structure after the inverted arch uplifted are checked,it can provide reference to evalute the stability of the lining structure.The results show that with the inverted arch lifted to a higher-position,the effects on the bending moment,axial force and deformation would become more significant,especially the effect on arch end is great.Much attention should be paid to such effects during construction.