摘要
秦岭深埋长距离引水隧洞极硬岩强度达到300 MPa以上,已成为制约隧洞掘进机(tunneling boring machine, TBM)高效施工的主要难题。针对秦岭引水隧洞极硬岩掘进施工问题,该文提出了基于TBM掘进隧洞的热能-机械耦合破岩方法,开展了有关微波、等离子体、火焰炬、水射流和钻孔劈裂的破岩试验以及数值计算和搭载设计,提出了5类辅助TBM破岩方法的适用性和搭载设计。研究结果表明:秦岭深埋引水隧洞岭南TBM掌子面岩体高含量石英吸收微波能力差、黑色极性矿物颗粒小,岩体微波劣化效应不显著,必须通过钻孔植入黑色极性矿物,增强岩体微波劣化效应;等离子体破岩方法采用超高电场密度能够产生显著的电力作用和热能破岩效果,可以将刀盘滚刀作为电极进行设计;火焰炬切割技术简单、易操作,但必须采取人工降温和热屏蔽措施;超高压水射流和钻孔超强劈裂破岩方法适用于掌子面岩体强度大于400 MPa, TBM掘进每日进尺小于1 m的工况。
Extremely hard rock with tensile strengths of more than 300 MPa were encountered in a deep, long diversion tunnel in the Qinling Mountains which significantly slowed the TBM excavation. This paper presents a coupled rock breakdown method using thermal energy and mechanical methods for extremely hard rock mass excavation without changing the TBM system. Attempts to break the extremely hard rocks included using microwaves supplemented by numerical simulations of using plasma jets to break the rocks. The present study analyzed the applicability of five kinds of rock breakdown methods. The results show that the rocks are extremely hard due to small black, polar mineral particles and the high quartz content in the rocks. The rocks could be weakened by injecting black, polar substances to improve the effect of microwave irradiation on the rocks. In addition, high voltage plasma jets were found to induce electrical-mechanical effects and thermal melting. The hob could be designed as electrodes. Flame cutting was easily used on the excavation face, but needs a thermal shield and cooling time after the cutting. Super high pressure water jets were also useful, but needed pressures of 400 MPa to cut the high tensile strength rock with excavation distances of less than 1.0 m per day.
作者
刘晓丽
孙欢
董勤喜
熊炎林
KUMAR Nawnit
苏岩
周建军
LIU Xiaoli;SUN Huan;DONG Qinxi;XIONG Yanlin;KUMAR Nawnit;SU Yan;ZHOU Jianjun(State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;School of Civil Engineering and Architecture,Hainan University,Haikou 570228,China;Survey Design&Research Institute,China Railway Tunnel Group Co.,Ltd.,Guangzhou 511400,China;Hanjiang to Weihe River Valley Water Diversion Project Construction Co.LTD.,Shaanxi Province,Xi'an 710010,China;State Key Laboratory of Shield Machine and Boring Technology,Zhengzhou 450001,China;China Railway Tunnel Group Co.,Ltd.,Guangzhou 511458,China)
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2022年第8期1292-1301,共10页
Journal of Tsinghua University(Science and Technology)
基金
国家自然科学基金项目(52079068,41941019,52109120)
水沙科学与水利水电工程国家重点实验室重大创新项目(2019-KY-03,2021-KY-04)。
关键词
深埋引水隧洞
TBM掘进
极硬岩
热能-机械破岩
deep-long division tunnels
TBM excavation
extremely hard rock
thermal-mechanical tunneling methods
