盾构隧道先隧后井工法对管片张开量影响的研究

发布时间：2018-03-28 21:27

本文选题：隧道工程　切入点：盾构隧道　出处：《岩石力学与工程学报》2014年S1期

【摘要】：为了研究盾构工程先隧后井施工法对盾构管片张开量的影响,在不易实测及不能通过试验获取的前提下,采用大型有限元分析软件对盾构施工过程进行三维弹塑性数值模拟,结合典型工程实例,分析先隧后井施工引起的管片张开量及其主要影响范围;分别探讨土体力学性质、土层局部加固及地下水位对管片张开量的影响。计算结果表明:先隧后井施工法引起管片张开,影响范围主要体现在距离工作井连续墙5环管片长度内,施工防渗分析可着重考虑近工作井4个接头处。管片张开量随着土层刚度的增大而减小,但不受土体强度指标的影响。对于先隧后井盾构施工可通过局部加固来有效地减小管片的张开量,进而防止渗漏。管片以上地层水位的存在对工作井相邻5环管片张开量影响显著,但水位的高低对张开量影响很小。建议采用先隧后井盾构施工时,对邻近连续墙5环管片长度范围内进行局部加固,以确保隧道施工运营安全。
[Abstract]:In order to study the influence of tunnel construction method on shield segment opening, the 3D elastoplastic numerical simulation of shield tunnel construction process is carried out by using large-scale finite element analysis software, which is not easy to be measured and can not be obtained by test. Combined with typical engineering examples, this paper analyzes the opening quantity of pipe piece and its main influence range caused by tunnel and well construction, and discusses the mechanical properties of soil respectively. The effect of local reinforcement of soil layer and underground water level on segment opening. The calculation results show that the length of pipe opening caused by the first tunneling and later well construction method is mainly within the length of 5 annular segments from the continuous wall of the working well. Construction impermeability analysis can focus on the four joints near the working well. The segment opening decreases with the increase of soil stiffness. However, it is not affected by the soil strength index. For the first tunnel and then the shield tunneling, the opening of the segments can be effectively reduced by local reinforcement. Therefore, the existence of formation water level above the segment has a significant effect on the opening of the adjacent five annular segments of the working well, but the water level has little effect on the opening. It is suggested that the first tunneling and then the shield tunneling should be used. In order to ensure the safety of tunnel construction, local reinforcement is carried out within the length range of 5 ring segments of adjacent continuous wall.
【作者单位】：华南理工大学土木与交通学院;
【基金】：国家水体污染控制与治理科技重大专项(2009ZX07423 004)
【分类号】：U455.43

【相似文献】