摘要
通过有限元模拟隧道台阶法施工,分析地表沉降、拱顶、拱底、横向变形和围岩最大、最小主应力随开挖步增长的变化规律,研究围岩变形特性和纵向影响范围,基于突变理论对拱顶沉降进行分析,研究围岩突变时机.结果表明:隧道开挖对掌子面的变形影响主要发生在拱顶、拱底及拱腰位置,地表沉降主要集中在隧道开挖中线附近,应力集中则发生在拱腰及拱脚处;影响范围主要集中在开挖面开挖方向前后1D(D为开挖洞径)范围内,其中开挖面前后0. 5D范围为强影响区,0. 5～1D范围为弱影响区.
The construction of tunnel with step method is simulated with finite element software to ana- lyze the surface subsidence, vault, arch bottom, lateral deformation and the maximum and minimum princi- pal stress of surrounding rock with the progress of the excavation step. And the deformation characteristics and vertical influence range of surrounding rock are studied; the vault settlement is analyzed by means of catastrophe theoiry the time of surrounding rock mutation is also studied. The result shows that the effect of deformation on the tunnel face mainly occurred in the vault, the arch bottom and arch waist position in tun- nel excavation; the surface subsidence is mainly concentrated near the center line in tunnel excavation; the stress concentration occurred at the arch and the toot of the arch ; the range of influence is mainly within the range of 1D before and after excavation. The area of excavation face 0.5D is the strong influence area, while the range of 0.5 ~ 1D is the weak influence area.
作者
厉广广
吴晨梦
LI Guangguang;WU Chenmeng(Jiangsu Province Transportation Engineering Construction Bureau,210000,Nanjing,China;Suining County Transportation Bureau,221200,Xuzhou,China)
出处
《北方工业大学学报》
2018年第5期135-139,共5页
Journal of North China University of Technology
关键词
隧道开挖
围岩
变形特性
影响范围
tunnel excavation
surrounding rock
deiormation characteristics
influence range
