摘要
以存在局部破碎带的青黄海底公路岩质隧道为例,考虑到海水的渗透性,采用有限元极限分析法分析海底隧道岩体注浆加固前、后的稳定性。计算结果表明,隧道整体是安全的,此种情况下,隧道衬砌原则上可按无水压设计,衬砌厚度与采用全水头设计相比可以大大降低。但当存在局部破碎带时,隧道安全系数降低,破碎带越宽,注浆堵水圈厚度越小,安全系数越小。与完整围岩破裂面位于两侧相比,含倾角45°破碎带围岩的稳定性最差。因此,必须做好破碎带的超前注浆堵水加固,以减少其渗水量,并对破碎带进行局部加固,此种情况下,隧道衬砌原则上可按有水压设计。
Considering the sea water seepage,limit analysis by finite element method is used to study the stability of a subsea tunnel in which the fracture zone exists. Result shows that the tunnel is safe for the intact surrounding rock. Under the condition,the lining of the subsea tunnel can be designed without water pressure;and the lining thickness can be reduced remarkably. The calculation results show that the fault-rupture zone decreases the stability of tunnel obviously. The wider the fracture zone is,the smaller the safety factor is. The thicker the rock grouting ring is,the larger the safety factor is. Slip surface of intact surrounding rock appears at both sides of tunnel;and the stability of rock mass in fracture zone with angle of 45°is the most unfavorable. So the pregrouting treatment is necessary in order to cut down the seepage water. Under this condition,the tunnel lining can be designed according to principle with water pressure.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2007年第S2期3751-3755,共5页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(50674059)
山东省自然科学基金资助项目(Y2005A03)
关键词
隧道工程
有限元极限分析
海底隧道
稳定性
破碎带
tunneling engineering
limit analysis by finite element method
subsea tunnel
stability
fracture zone
