供水系统地震风险评估及升级优化

Risk evaluation and optimization of water supply system under earthquake

摘要:

为了评估供水系统地震风险和确定关键供水管道,建立了系统震后供水率S、管道升级收益指数U和管道断裂影响指数B 3项评价指标,并运用基于蒙特卡洛仿真的地震作用下流体的图解迭代响应分析(GIRAFFE)方法对供水系统在地面峰值速度vG=50 cm/s时进行了风险分析．仿真结果表明,S的分布特征与节点的用水需求分布关系密切,U能作为首要指标并通过一次运算来确定系统中的单个关键供水管道和最大收益管道组合,它是管道断裂影响指数和管道断裂程度共同作用的结果．由单个关键供水管道组成的升级组合并不是最佳的升级优化策略,升级最大收益管道组合能最大程度地提高系统震后供水绩效并降低地震风险．

Abstract:

To evaluate seismic risk and identify critical pipelines of water supply system, water supply index(S), pipeline update profit(U) and pipeline break consequence(B) are set up to describe system seismic performance, and the graphical iterative response analysis of flow following earthquakes (GIRAFFE) based on Monte Carlo simulation is applied to the hypothetical water supply system for peak ground velocity vG=50 cm/s. The simulation result shows that the distribution of S is related to nodes’ demand pattern in the system. Calculated by running single Monte Carlo simulation, U could be used as primary indicator to identify individual critical pipelines and maximum benefit portfolio, and it is the consequence of B and pipelines’ damage probability. Updating the group with largest individual critical pipelines is not the best strategy for the system,and the system seismic performance would be most improved by updating maximum benefit portfolio.