基于突变理论的泥岩隧道稳定性及极限位移确定  

Stability and Ultimate Displacement Determination of Mudstone Tunnel Based on Catastrophe Theory

作　　者：曹明星 严松宏[1] 杜嘉轩 CAO Mingxing;YAN Songhong;DU Jiaxuan(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学土木工程学院,兰州730070

出　　处：《兰州交通大学学报》2024年第1期8-15,共8页Journal of Lanzhou Jiaotong University

摘　　要：为了分析第三系富水砂泥岩隧道的稳定性和极限位移的确定,应用突变理论尖点突变模型推导了隧道拱顶下沉的突变判别方程。采用数值模拟对隧道进行开挖,通过改变围岩应力释放系数,找出围岩相应节点塑性应变、速度和加速度的突变点,进而来判断隧道极限位移值。得出第一部开挖,围岩应力释放率为75%时,塑性应变加速度出现突变点,拱顶下沉为17.06 cm;第二部开挖时,围岩应力释放率为75%时,塑性应变加速度出现突变点,拱顶下沉为19.77 cm;第三部开挖时,围岩应力释放率为65%时,塑性应变加速度出现突变点,拱顶下沉为24.77 cm;第四部开挖时,围岩应力释放率为60%时,塑性应变加速度出现突变点,拱顶下沉为25.52 cm;第五部开挖时,围岩应力释放率为50%时,塑性应变加速度出现突变点,拱顶下沉为25.87 cm;第六部开挖时,围岩应力释放率为45%时,塑性应变加速度出现突变点,拱顶下沉为25.93 cm。In order to analyze the stability and limit displacement of the Tertiary water-rich sand mudstone tunnel,the abrupt discriminant equation of tunnel vault subsidence is derived by applying the abrupt point abrupt model of ab-rupt theory.By changing the stress release coefficient of surrounding rock,the abrupt points of plastic strain,velocity and acceleration of the corresponding joints of surrounding rock are found out,and then the ultimate displacement value of the tunnel is judged.The results show that when the stress release rate of surrounding rock is 75%,the sud-den acceleration of plastic strain appears,and the arch roof subsidence is 17.06cm.In the second part of excavation,when the stress release rate of surrounding rock is 75%,the acceleration of plastic strain appears a sudden point,and the arch roof subsidence is 19.77 cm.In the third part of excavation,when the stress release rate of surrounding rock is 65%,the acceleration of plastic strain appears a sudden point,and the arch roof subsidence is 24.77 cm.In the fourth part of excavation,when the stress release rate of surrounding rock is 6o%,the acceleration of plastic strain appears a sudden point,and the arch roof subsidence is 25.52 cm.In the fifth part of excavation,when the stress re-lease rate of surrounding rock is 50%,the acceleration of plastic strain appears a sudden point,and the arch roof sub-sidence is 25.87cm.When the stress release rate of the surrounding rock is 45%,the acceleration of plastic strain ap-pears a sudden point and the vault subsidence is 25.93 cm.

关 键 词：砂泥岩 数值模拟 尖点突变模型 应力释放 隧道极限位移 

分 类 号：TU435[建筑科学—岩土工程]