引汉济渭工程泄水系统失效风险计算

引汉济渭工程涉及提水系统工程、蓄水系统工程和输水系统工程,工程受自身因素和外界因素的作用使得系统功能存在失效风险。蓄水系统工程的安全涉及挡水系统和泄水系统的安全,泄水系统功能的正常发挥是工程安全的重要保证。以引汉济渭工程泄水系统风险防控为目标,以风险事件为基础,基于故障树对风险的成因进行分析,建立系统失效的贝叶斯网络,并根据风险特性合理选择可靠的风险率计算方法,运用贝叶斯网络的推理能力,构建引汉济渭工程泄水系统失效风险计算的理论体系。以引汉济渭工程三河口水库的泄水系统为研究对象,基于蒙特卡洛模拟和可靠度理论计算出系统部件的失效风险率,运用贝叶斯网络推理得出系统失效的风险率,采用情景分析的方法得出泄水系统安全的主要风险因素为漂浮物和渗漏。漂浮物和渗漏的失效风险率增加50%,泄水系统的失效风险率增加1.35×10-5。若泄水系统风险率降低为0,漂浮物和渗漏的失效风险需降低1.35×10-5;若泄水系统失效,漂浮物和渗漏的失效风险为1.82×10-1。结果表明贝叶斯网络理论体系能够对工程的泄水系统风险进行动态识别、评估和控制,对水利工程的风险管理具有一定的指导意义。

Failure risk calculation of water-discharge system for Hanjiang-to-Weihe River Valley Water Diversion Project

As Hanjiang-to-Weihe River Valley Water Diversion Project involves water-pumping system works，water-storage system works and water-conveyance system works，failure risks of the system functions are there for the project due to itself factors and the relevant external factors. The water-storage system works is related to the safeties of water-retaining system and water-discharge system works，while the normal exertion of the function of the water-discharge system is an important guarantee of the project safety. By taking the prevention and control of the risk from the water-discharge system of Hanjiang-to-Weihe River Valley Water Diversion Project as the target，Bayesian network for the failure of the system is established herein based on the analysis of the risk causations made by the methodoffaulttree analysis according to the relevant risk events，and then the reliable calculation method of risk rate is reasonably selected in accordance with the relevant risk characteristics and the theoretical system for the failure rick calculation of the water-discharge system of Hanjiang-to-Weihe River Valley Water Diversion Project is built up with the reasoning capacity of Bayesian network. By taking the water-discharge system for Sanhekou Reservoir of Hanjiang-to-Weihe River Valley Water Diversion Project as he study object，the failure risk rates of the system components are calculated with Monte Carlo Simulation and reliability theory，the failure risk rate of the system is obtained through Bayesian network reasoning and it is obtained with the method of scenario analysis that the main risk factors of the water discharge system are floating debris and leakage. If the rate of the failure risk from floating debris and leakage is increased by 50% ，the failure risk rate of the water-discharge system is to be increased by 1. 35 × 10 － 5. If the failure risk rate of the water-discharge system is decreased to 0，the failure risk from floating debris and leakage is necessary to be decreased by 1. 35 × 10 － 5. Meanwhile，if the water-discharge system fails，the failure risk from floating debris and leakage is 1. 82 × 10 － 1 . The study result shows that the theoretical system of Bayesian network can dynamically identify，evaluate，decrease and control the risks from the discharge system of the project，thus has a certain guiding significance for the risk management of water conservancy project.