考虑地震动空间变化的区域公路网连通可靠性研究

Connectivity Reliability of Regional Highway Network Considering Spatial Variation in Seismic Ground Motion

区域公路网是社会交通大动脉和地震灾害救援生命线,连通可靠性反映了地震灾害发生后公路网的通行能力,地震动受震源位置及震中距的影响而具有显著的空间变化,对公路网的震后破坏状态具有重要影响。以邯郸地区公路网为研究对象,通过设定震源位置与震级,研究地震动空间变化影响下的区域公路网连通可靠性。首先,设定邯郸市1830年磁县大地震及一个虚拟地震为地震情景,分别设置震级为M6.0、6.5、7.0和7.5,基于地震动衰减关系表达地震动空间变化,得到公路单元对应的PGA。然后,结合地震易损性模型分析公路单元震后通行概率。最后,针对区域公路网空间范围大的典型特征,优化城市道路所用的最大可能状态算法,对邯郸地区公路网进行连通可靠性评估。结果表明,区域尺度下公路网络单元和节点数量多、空间展布复杂,其抗震连通可靠性与既有公路分布、区域城市位置等因素密切相关,地震动空间变化显著影响公路单元的震后破坏状态和通行概率,研究成果可为区域尺度公路网地震灾害评估及抗震韧性研究提供参考。

Regional highway network serves as the primary artery of social transportation and the lifeline for earthquake disaster rescue.Connectivity reliability reflects the traffic capacity of the highway network following seismic hazards.Ground motions exhibit significant spatial variation influenced by the source location and epicentral distance,which have a crucial impact on the post-earthquake damage status of highway network.This study adopted the highway network in Handan area,to investigate the connectivity reliability under the influence of spatial variation in ground motions by setting seismic source locations and magnitudes.First,the 1830 Cixian earthquake and a virtual earthquake in Handan City were taken as earthquake scenarios,with the magnitudes of M6.0,6.5,7.0 and 7.5,respectively.The spatial variation of ground motions was expressed based on attenuation relationships to obtain the Peak Ground Acceleration(PGA)corresponding to highway units.Then,the post-earthquake traffic probabilities of highway units were analyzed in conjunction with the seismic vulnerability models.Finally,considering the typical characteristics of the wide spatial scale of the regional highway network,an optimization of the maximum possible state algorithm used for urban roads was conducted to evaluate the connectivity reliability of the highway network in Handan area.The results demonstrate that the regional highway network contains a huge number of units and nodes with a complex spatial distribution.Additionally,the seismic connectivity reliability is closely related to existing road distributions and regional urban locations.The spatial variation of ground motions significantly influences the post-earthquake damage status and traffic probabilities of highway units.In conclusion,the research findings provide references for seismic disaster evaluation and resilience analysis of regional highway network.