盾构下穿棚户区的风险辨识与控制对策研究

Research on Risk Identification and Control Measures to Shield Underneath Crossing Shantytowns

盾构施工过程中,如何安全平稳的下穿老旧棚户区一直是亟待解决的工程技术难点。通过对下穿老旧棚户区施工运用了一种故障树风险分析方法,将控制地表沉降量作为风险分析的核心,逐层找出引起棚户区塌陷或损坏的风险源,提出了掌子面不稳、盾构偏航、盾构施工参数选取不当等需要重视和规避的风险基本事件,并对基本事件的概率大小进行了排序,选取风险概率最大的三个风险源,提出控制预防和处理的方案,实施规避措施。以提出的控制对策反馈到实际施工过程中,对控制老旧棚户区的地表沉降起到良好的积极作用,从而保护老旧棚户区的建筑结构稳定。

How to safely and smoothly underneath crossing the old shantytowns has always been an urgent engineering problem in the construction of the shield.By applying a fault tree risk analysis method is made on the construction of the old shanty towns and the control the amount of ground subsidence as the core of the risk analysis,layer by layer,to identify risk factors that cause collapse or damage of shanty towns.The basic events of risk that need to be emphasized and avoided are found,such as unsteady tunnel face,yawing of the shield and improper selection of shield construction parameters.In accordance with the probability of sorting out the basic events to sort,select the risk probability of the top three and put forward the control of prevention and treatment programs and implementation of circumvention measures.The proposed control strategy is fed back to the actual construction process,it plays a positive role in controlling surface settlement in the old shanty towns,in order to protect the stability of the old shantytowns’ building structures.