基于蒙特卡罗法的城市燃气管网抗震连通可靠性分析

Analysis of Anti-seismic Connectivity Reliability of City Gas Pipeline Nework Based on Monte Carlo Method

在对燃气管道进行地震反应判别的基础上,计算管道的抗震可靠度,并结合图论将城市燃气管网简化为源点、汇点和边线,建立管网简化模型。采用蒙特卡罗法对某六节点网络模型进行抗震连通可靠性分析,结果表明：随着迭代次数的增加,近似解以更小的误差接近精确解的概率更大;迭代次数取为5 000时,能够较好地满足精度要求。通过对连通性矩阵进行分析,探讨了设定源点提高目标汇点连通可靠度的可行性。最后,以保定市区的大型燃气管网为例,计算了Ⅶ~Ⅸ度地震烈度下管网的连通可靠度,对比了设定源点对汇点连通可靠度的影响,为该市燃气管网的震害预测和抗震优化提供参考。

Based on discriminating the seismic response of gas pipeline, we calculated the anti-seismic reliability of the pipe, and combined with graph theory, we simplified the city gas pipeline network as the source point, sink point and sideline to establish the simplified model of pipeline network. Then we analyzed the anti-seismic con- nectivity reliability of a certain six-node network model by Monte Carlo method. The results showed that with the increasing of iterations number, the probability of the approximate solution close to the exact solution with a smaller error is greater. Setting the number of iterations as 5 000 could better meet the precision requirement. Based on the analysis of the connectivity matrix, we discussed the feasibility of improving the connectivity reliability of the target sink point by using the setting source point. At last, taking the large-scale gas pipeline network in downtown Baoding as an example, we calculated the connectivity reliability of pipeline network under earthquake intensities from Ⅶ to Ⅸ degree, and compared the impact of the setting source point on the connectivity reliability of all the sink nodes, which could provide references for the seismic damage prediction and antiseismic optimization of gas pipeline network in the study city.