摘要
穿越高大山体的隧道TBM施工不可避免地会遇到高地应力问题,研究地应力对TBM滚刀破岩机制和掘进效率的影响具有重大的工程价值和科学意义。通过理论分析和UDEC数值模拟技术对围压作用下滚刀破岩模式进行研究,发现围压对滚刀破岩过程影响比较复杂:围压对粉碎区深度和裂纹扩展区内滚刀作用方向的裂纹扩展起到抑制作用;而对围压作用方向的裂纹扩展有促进作用,表现为边裂纹的扩展范围会更大,扩展路径会更加平直,发展更加迅速,滚刀间岩片的形成更加容易。TBM现场掘进试验表明,地应力越高,围压作用越明显,TBM破岩更加容易,掘进效率会更高。从TBM滚刀作用下岩片形成的难易程度角度考虑,理论分析、数值模拟和TBM现场掘进试验都表明围压作用促进TBM滚刀破岩。
TBM tunnels through the high mountain will inevitably encounter high stress problem,and the research on the influence mechanism of high stress on TBM breakage is very important. The influence of confining pressure on rock fragmentation by TBM cutters is successfully studied by using mechanical analysis and numerical simulation,and it implies that the impact of confining pressure is very complicated. The depths of crushed zone and lengths of cracks parallel to normal force decrease with increasing confining pressure,but confining pressure facilitates rock fragmentation and promotes chipping process,and the side cracks will develop rapidly and smoothly. The TBM in-situ penetration experiment shows that the rock is excavated more easily by TBM with increasing confining pressure. Considering the difficulty of rock chipping by TBM cutters,the results of mechanical analysis and numerical simulation and TBM in-situ penetration experiment all prove that confining pressure is favorable to TBM cutter breakage and penetration.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2014年第S1期2743-2749,共7页
Chinese Journal of Rock Mechanics and Engineering
基金
国家建设高水平大学公派留学生项目
关键词
隧道工程
TBM
滚刀
破岩机制
围压
地应力
tunneling engineering
TBM
cutter
rock breakage mechanism
confining pressure
in-situ stress
