基于云模型与证据理论的大坝安全综合评估方法

大坝工作性态影响因素众多、属性的特征多样、相互关系复杂,对其安全状况的综合评估是一个典型的不确定性问题。充分考虑大坝安全评估过程中的模糊性和随机性,组合应用云模型和DS证据理论开展了大坝安全多指标综合评估方法研究。依据大坝安全评估多指标体系和安全等级划分标准,借助云模型实现D-S证据理论中基本概率赋值,进而基于D-S证据理论并加以改进,构建了大坝安全综合评估模型,并提出了相应的综合评估实现方法。应用于实际工程案例分析,验证了文中所述方法的合理性与可行性。实例表明,通过云模型和D-S证据理论在大坝安全综合评估中的组合使用,有效降低了评估过程不确定性对其结果的影响,为大坝安全多指标综合评估提供了一种可行的途径和思路。

Cloud model and evidence theory based method for comprehensive assessment on dam safety

There are so many factors of impacts on the working behavior of dam，of which the characteristics of their attributes are diverse with complicated inter relationships among them，thus the comprehensive assessment on its safety condition is just a typical uncertainty question. Under full consideration of both the fuzziness and randomness in the process of the safety assessment on dam，a multi index comprehensive method for dam safety assessment is studied herein by combining cloud model with D-S evidence theory. In accordance with the multi index system of dam safety assessment and the safety classification standard，the determination of the basic probability assignment in D-S evidence theory is realized with cloud model，and then is improved based on D-S evidence theory，with which a dam safety comprehensive assessment model is made up，while the corresponding method to realize the comprehensive assessment is put forward as well. The reasonability and feasibility of the method mentioned herein are verified through its application to the analysis made on an actual engineering case. The actual case shows that through the combined use of both cloud model and D-S evidence theory，the impact from the uncertainty on its result during the process of the assessment is effectively lowered，thus a feasible way and idea is provided for the multi index comprehensive assessment on dam safety.