高层建筑软土深基坑施工风险管理研究

发布时间：2018-08-23 08:11

【摘要】：随着我国经济发展和工程技术的进步,高层及超高层建筑工程不断涌现,地下空间不断被开发利用,对深基坑施工技术要求越来越高,施工难度也就越来越大。基于深基坑工程建设项目特点,施工过程中会存在着很多不确定性因素从而导致各种风险,如果施工风险管理不当,将造成严重后果。尽可能地提高深基坑施工风险管理水平,降低其事故发生率以及事故损失,已经成为一个迫切需要深刻探究的研究课题。本文在理论分析的基础上,采用故障树分析方法对高层软土深基坑风险问题进行研究,构建一套完备的软土深基坑故障树理论,在传统故障树分析的基础之上,采用贝叶斯网络对其进行改进,解决传统故障树分析过程中,分析繁琐、概率求解效率底下的问题,并采用专家调查法对基本底事件基本概率进行评判,以达到风险识别、风险预警的目的。在此基础上,提出符合工程特点的风险应对措施,保证结构施工安全。通过调研,本文构建完善的故障树分析体系,从工程技术与人员意识两方面出发,首次构建一套由1个顶事件、15个中间事件、33个底事件形成的故障树分析完备网络系统图例;对传统的故障树分析系统进行贝叶斯网络改进创新,采用子节点概率表等代的手段,换算两者之间的概率关系,并构建贝叶斯网络,改进的算法计算效率高、算法简单,有助于快速分析风险顶事件概率,且能够直观得出中间节点的相应概率;采用传统的故障树法对底事件关联度进行分析,得到与顶事件关联度最高的底事件,有助于通过控制底事件发生概率,从而避免顶事件失效情况的发生;对底事件基本概率采用专家调查法进行评定,创新提出根据专家知识储备,增加专家专业权重的概念。通过本文对深基坑施工风险管理的研究,不仅能够加强对深基坑施工过程中的风险控制,减少深基坑工程事故的发生,确保工程项目安全顺利进行,同时采用数学算法模式,构建完备概率计算模型,并对已有模型进行创新改进,以期得到高效评判手段,快速进行风险管理与控制。
[Abstract]:With the development of our economy and the progress of engineering technology, high-rise and super-high-rise building projects are constantly emerging, and underground space is constantly being developed and utilized. The construction technology of deep foundation pit is becoming more and more demanding and the construction difficulty is becoming more and more difficult. Based on the characteristics of deep foundation pit construction project, there will be many uncertain factors in the construction process, which will lead to various risks. If the construction risk is not properly managed, it will cause serious consequences. It has become an urgent research topic to improve the risk management level of deep foundation pit construction and reduce the accident rate and accident loss as far as possible. On the basis of theoretical analysis, this paper uses fault tree analysis method to study the risk of deep foundation pit in high-rise soft soil, and constructs a set of complete fault tree theory of soft soil deep foundation pit, which is based on the traditional fault tree analysis. The Bayesian network is used to improve it to solve the problem of complicated analysis and low efficiency probabilistic solution in the process of traditional fault tree analysis. The basic probability of the basic bottom event is evaluated by expert investigation method in order to achieve risk identification. The purpose of risk warning. On the basis of this, the paper puts forward the measures to deal with the risks in accordance with the characteristics of the project to ensure the safety of the construction of the structure. Through investigation and investigation, this paper constructs a perfect fault tree analysis system, starting from two aspects of engineering technology and personnel consciousness, constructs a complete network system legend of fault tree analysis, which is composed of 1 top event, 15 intermediate events and 33 bottom events for the first time. In the traditional fault tree analysis system, the Bayesian network is improved and innovated. The probability relation between the two is converted by means of sub-node probability table, and the Bayesian network is constructed. The improved algorithm has high computational efficiency and simple algorithm. It is helpful to analyze the probability of risk top event quickly, and to get the corresponding probability of intermediate node intuitively; to use the traditional fault tree method to analyze the correlation degree of bottom event, and to get the bottom event with the highest correlation degree of top event. It is helpful to avoid the failure of top event by controlling the probability of bottom event. The basic probability of bottom event is evaluated by expert investigation method, and the concept of increasing expert weight according to expert knowledge reserve is put forward. Through the study of risk management in deep foundation pit construction in this paper, not only can the risk control in deep foundation pit construction process be strengthened, but also the accidents of deep foundation pit construction can be reduced, and the safety and smooth progress of engineering project can be ensured. At the same time, the mathematical algorithm model is adopted. The complete probability calculation model is constructed, and the existing model is innovated and improved in order to obtain the efficient evaluation method and to carry out risk management and control quickly.
【学位授予单位】：湖北工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU753;TU71

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