摘要
通过数值模拟法对隧道施工全过程进行了三维弹塑性分析,尤其对不同施工条件下的隧道竖直位移变化进行了分析。结果表明:在掘进面到达前,围岩会产生前期位移收敛,本算例前期位移量为总位移量的32.7%;隧道变形受围岩级别、埋深及半径的影响,围岩劣化条件下的位移增量主要发生在隧道断面开挖前,半径增大条件下的位移增量主要发生在隧道断面开挖后;Ⅴ级围岩条件下,前期位移量显著增大;隧道变形稳定所需距离主要受半径的影响,稳定距离S与半径R关系式为S≈1.2R。
A 3 D finite element analysis is conducted to simulate the conventional procedure of tunnel excavation , especially the tunnels vertical displacement change when tunnel is constructed under different conditions is analyzed. The results prove that there is a preconvergence displacement ahead of the excavation face and its value account for 32.7% in the maximum displacement value in this case. For the influence of surrounding rock, burying depth and radius effect,the displacement caused by surrounding rock deterioration mainly occurred ahead of the excavation face,and displacement caused by the radius increasing mainly occurred behind the face. The preconvergence displacement increases apparently inⅤ-degree soft rock. The distance of deformation stability increases with increasing radius, and the relationship is S≈1？2R.
出处
《施工技术》
CAS
北大核心
2014年第18期69-73,共5页
Construction Technology
基金
陕西省重点科技创新团队资助项目(2013KCT-015)
陕西省自然科学基金资助项目(2013JQ7010)
关键词
隧道工程
掘进效应
前期收敛
有限元分析
tunnels
excavation disturbance
preconvergence
finite element analysis
