土石坝的安全风险评估研究

发布时间：2018-12-13 14:01

【摘要】：中国是世界上拥有大坝数量最多的国家，中国共建水库大坝8.5万座，土石坝占其中的93%。大多数的土石坝都是20世纪80年代以前建筑，由于受到当时技术的限制，很多土石坝的设计和施工都不完善，且都没有经过严格的质量审查。经过几十年的运行，多数的土石坝都存在各种大大小小的病险，土石坝处于不同程度的病险状态下运行，，危及到下游人民的生命财产和经济建设。为此需要对大坝的安全风险进行评估，判断大坝是否处在安全的等级状态下运行。论文的研究内容及成果如下： (1)根据《水库大坝安全评价导则》(SL258-2000)对大坝系统的分类，将大坝系统分为工程质量、大坝运行管理、防洪标准复核、结构安全、渗流安全、抗震安全复核、金属结构安全七个子系统，论文在《水库大坝安全评价导则》的基础上将土石坝风险指标细分为目标层、准则层和因素层，建立三层的土石坝风险指标体系，以便更全面和深入地研究土石坝安全风险状况。 (2)对土石坝风险指标定量，论文依据《水库大坝安全评价导则》中对各子系统的评价细节要求，制定了风险指标的定量标准。首先通过对风险指标的定性描述，结合专家经验法，最后完成对风险指标的定量。 (3)采用模糊层次分析法计算风险指标的权重值，再通过集对分析法和可变模糊集法对土石坝各级进行建模评估。首先参考《水库大坝安全评价导则》和其他相关文献，将土石坝安全风险评估分为五个安全等级；再分别以集对分析法和可变模糊集法对土石坝指标系统进行建模分析，计算出土石坝和各子系统的评估结果，分析各安全等级的评估结果，判断土石坝处于什么安全级别。结合某实例水库，计算得出实例土石坝安全风险等级与提供的水库安全报告的安全级别一致，说明了集对分析法和可变模糊集法对土石坝的安全风险评估是合理和可行的，得出的评估结果对土石坝的运行管理有预警作用。
[Abstract]:China has the largest number of dams in the world, with 933 earth-rock dams accounting for 85000 dams. Most earth-rock dams were built before 1980s. Due to the limitation of technology at that time, the design and construction of many earth-rock dams are not perfect and have not been subjected to strict quality review. After several decades of operation, most earth and rock dams have a variety of hazards, large and small. The earth and rock dams run under different degrees of disease risk, endangering the lives and property of the downstream people and economic construction. Therefore, it is necessary to evaluate the safety risk of the dam and determine whether the dam is running under the safety grade. The research contents and results are as follows: (1) according to the classification of dam system by SL258-2000, the dam system is divided into engineering quality, dam operation management, flood control standard review. Structural safety, seepage safety, seismic safety review and metal structure safety are seven subsystems. On the basis of "dam safety evaluation guidelines for reservoirs", the risk index of earth-rock dams is divided into target layer, criterion layer and factor layer. In order to study the safety risk of earth-rock dam more comprehensively and deeply, the risk index system of three layers earth and rock dam is established. (2) for the risk index of earth-rock dam, the quantitative standard of risk index is established according to the detailed evaluation requirements of each subsystem in the "guidelines for dam safety evaluation of reservoirs". Firstly, the quantitative analysis of risk index is finished by qualitative description of risk index and expert experience. (3) using fuzzy analytic hierarchy process (FAHP) to calculate the weight value of risk index, and then using set pair analysis method and variable fuzzy set method to model and evaluate each grade of earth-rock dam. Firstly, the safety risk assessment of earth-rock dam is divided into five safety grades by referring to "guidelines for dam safety evaluation" and other relevant documents. Then the index system of earth-rock dam is modeled and analyzed by set pair analysis method and variable fuzzy set method, the evaluation results of earth and rock dam and each subsystem are calculated, the evaluation results of each safety grade are analyzed, and the safety level of earth-rock dam is judged. Combined with an example reservoir, the safety risk grade of earth-rock dam is consistent with that of the reservoir safety report, which shows that the assessment of safety risk of earth-rock dam by the method of set pair analysis and variable fuzzy set is reasonable and feasible. The result of evaluation has early warning effect on operation and management of earth-rock dam.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV641;TV698.1

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