地铁盾构施工地面沉降风险分析

发布时间：2018-11-08 15:22

【摘要】：鉴于地铁工程的复杂性,在施工过程中极易发生事故,其中就包括严重地面沉降带来的地面塌陷、临近建筑物及管线损坏等等。地铁施工不可避免地带来地面沉降,严重地面沉降具有极大的危害性,因此,对地铁盾构施工中的地面沉降进行风险管理,有助于预防及避免施工过程中出现严重地面沉降,减少财产损失和安全风险,具有重要的实用价值。论文首先梳理了多篇国内外有关地铁盾构施工地面沉降的研究文献,总结出地铁盾构施工地面沉降影响因素;本文将地面沉降分为“安全”和“严重地面沉降”两态,并采用动态故障树建立地铁盾构施工地面沉降风险评估模型,然后将该模型模块化并求解,如此便可风险概率;接下来文章对影响因素进行敏感性分析以进行关键因素辨识,通过文章的分析可知地铁盾构施工地面沉降影响因素间并不是相互独立的,会相互影响,为了考虑因素间的相互影响,本文选取基于EFAST的全局敏感性分析方法来进行地面沉降影响因素敏感性分析。最后结合工程实例,运用动态故障树进行地铁盾构施工地面沉降风险预测,并通过基于EFAST的全局敏感性分析寻找地面沉降的关键影响因素。结果表明,随着施工时间的延长,发生严重地面沉降的风险逐渐增大;并且得出隧道设计参数对地面沉降影响最大,土层参数次之;得出的结果符合工程实际,说明了本文所选方法在地铁盾构施工地面沉降风险分析方面的可行性。本文采用动态故障树进行地铁盾构施工地面沉降风险预测和基于EFAST的全局敏感性分析来进行关键因素辨识,为地铁盾构施工地面沉降风险管理的研究提供了新思路。
[Abstract]:In view of the complexity of subway engineering, accidents are easy to occur in the construction process, including ground collapse caused by serious land subsidence, damage to adjacent buildings and pipelines, and so on. The subway construction inevitably brings about the land subsidence, and the serious ground subsidence has great harmfulness. Therefore, the risk management of the ground settlement in the subway shield construction is helpful to prevent and avoid the serious land subsidence in the construction process. It has important practical value to reduce property loss and safety risk. In this paper, firstly, many literatures about ground subsidence in shield construction of subway are reviewed, and the factors affecting ground subsidence in shield construction of subway are summarized. In this paper, the ground subsidence is divided into "safety" and "serious ground subsidence", and dynamic fault tree is used to establish the risk assessment model of ground subsidence in shield construction of subway, and then modularize the model and solve it, so that the risk probability can be solved. Then the paper analyzes the sensitivity of the influencing factors in order to identify the key factors. Through the analysis of the paper, it can be concluded that the factors affecting the ground subsidence in shield tunneling construction are not independent of each other, but will affect each other. In order to consider the interaction between the factors, the global sensitivity analysis method based on EFAST is selected to analyze the sensitivity of the influence factors of land subsidence. Finally, the dynamic fault tree is used to predict the risk of ground subsidence in shield tunneling, and the key factors of land subsidence are found through the global sensitivity analysis based on EFAST. The results show that, with the extension of construction time, the risk of serious land subsidence increases gradually, and the tunnel design parameters have the greatest influence on the land subsidence, followed by the soil parameters. The results are in line with the engineering practice, which shows the feasibility of the method selected in this paper in the analysis of the ground subsidence risk in the shield tunneling construction of subway. In this paper, the dynamic fault tree is used to predict the risk of ground subsidence in shield construction of subway and the global sensitivity analysis based on EFAST is used to identify the key factors, which provides a new idea for the study of risk management of ground subsidence in shield construction of subway.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U231.3;U455.43

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