In order to study the effect of horizontal rotary jet grouting pile plus advanced small pipe combination pre-reinforcement in the rich water sand layer tunnel,based on a section of the Qingdao Metro tunnel,the finite element numerical simulation method was used to compare and analyze the rein-forcement effect of three working conditions:non-pre-reinforcement,using horizontal rotary jet grouting pile alone,and rotary jet grouting pile combined with advanced small pipe combination pre reinforce-ment.The results show that compared with the non-pre-reinforcement scheme,the use of horizontal ro-tary jet grouting pile pre-reinforcement alone can reduce surface settlement,arch settlement,and lon-gitudinal displacement of the palm face by about 61%,59%,and 38%,respectively.The combination of horizontal rotary jet grouting pile and advanced small conduit pre reinforcement scheme can reduce surface settlement,arch crown settlement,and longitudinal displacement of the palm face by about 66%,77.6%,and 38.9%,respectively.The groundwater seepage flow at typical excavation sections and arch feet can be reduced by 93.4% and 96.7%,respectively.The pre-reinforcement effect and wa-ter stop effect are significant.
horizontal jet grouting pilewater-rich sandnumerical simulationeffect of water stoppre-reinforcement
NETL
NSTL
万方数据
