盾构隧道下穿高速公路加宽区管桩施工技术

以郑州地铁3号线出入场线-新柳路站盾构施工为工程背景。研究小半径、大纵坡、浅覆土盾构隧道下穿高速公路加宽区管桩的施工技术。本文将盾构下穿高速公路加宽区分为三个过程,即盾构机达到管桩前、盾构机下穿管桩过程中和盾构机穿过管桩后进行研究。在盾构机到达管桩前设试推段,以确定适当的土仓压力、掘进速度和同步注浆参数;在盾构下穿管桩过程中调整适当的推进方向和姿态控制、管片拼装、注浆参数和防渗措施;以及对盾构穿过管桩后的监测及加固措施等进行研究,有效地保证了隧道的成型效果及盾构施工的顺利进行。

Construction technology of pipe pile under shield tunnel in highway widening zone

The shield tunnel construction of xinliu road station,the exit and entrance line of zhengzhou metro line 3,is taken as the engineering background.This paper studies the construction technology of tunnel with small radius,large longitudinal slope and shallow overburden through the widened area of expressway.In this paper,the widening of the shield tunneling expressway is divided into three processes,namely,before the shield tunneling machine reaches the pipe pile,in the process of the shield tunneling machine penetrating the pipe pile and after the shield tunneling machine penetrating the pipe pile.In order to determine the appropriate propulsive pressure,propulsive speed and synchronous grouting parameters,a push section is set up before the shield machine reaches the pipe pile.In the process of tunneling through the pipe pile under the shield tunneling,the appropriate propulsion direction and attitude control,piece assembly,grouting parameters and anti-seepage measures should be adjusted.As well as the research on the monitoring measurement and reinforcement measures after the shield tunneling passes through the pipe pile,which effectively guarantees the forming effect of the tunnel and the smooth progress of the shield tunneling construction.