土压平衡盾构洞内拆机技术方案研究

Study on Technical Scheme of EPB Shield Underground Disintegration

洞内拆机技术广泛应用于接收条件受限的盾构隧道工程中,但目前部分洞内拆机作业中仍存在标准化水平低、对盾构机破坏性大等缺陷。结合大量实际工程案例,将土压平衡盾构洞内拆机工程总结为井下拆机工程与原位拆机工程两类,提出“以拆机工程定型为首,盾构结构设计、拆机工作、运输工作三重点结合”的拆机工程理念,归纳总结了拆机工程中盾体、刀盘、主驱动、螺旋运输机、管片安装机等关键部件的优化拆解方案,并对各方案在两类拆机工程中的适用性展开研究;针对原位拆机工程中的难点问题螺旋运输机及主驱动拆除,提出详细的工艺流程,为两类拆机工程分别总结了一套标准化水平高、破坏性小的拆机流程方案;分析了两类拆机工程中的施工风险,并提出了相应安全保障措施。

The technology of underground disintegration for shield has been widely used in shield tunnel engineering with limited receiving conditions.At present,some shield underground disintegration operations still have defects such as low standardization level and great damages to shield machines.Combined with a large number of actual shield underground disintegration projects,this paper summarizes the shield disintegration projects into shield disintegration projects in the construction well and shield disintegration projects in the tunnel.The concept,that determining the type of shield underground disintegration project comes the first,followed by the combination of three key processes of shield structure design,demolition and transportation,is put forward.The optimal disintegration schemes of shield body,cutter head,main bearing,screw conveyor,segment installer and other key components in the disintegration project are summarized.The applicability of each scheme in the two types of shield disintegration projects is studied.Aiming at the difficult problems in the disintegration of main bearing and screw conveyor in the shield tunnel,detailed technological processes are presented.For the two types of shield disintegration projects,a set of disintegration process schemes with high standardization level and less damage are summarized respectively.The construction risks in the two types of disintegration projects are analyzed,and corresponding safety guarantee measures are proposed.