Resilience Assessment Of Urban Bridge Network Considering The Traffic Impact

The earthquake is one of the most serious threats to transport infrastructure,and in recent years many violent earthquakes in the world have caused major damage to infrastructures.As the link between economic and social development and the indispensable infrastructure in the “Belt and Road”,bridge network system plays an important role.However,serious damages are found in bridge structures and traffic networks in previous earthquakes,which have a significant impact on the earthquake evacuation,organizing rescue and post-disaster reconstruction.Resilience is an indicator parameter that assesses the recoverability of structures or systems.It can reflect the ability of the structure or system to recover quickly and resist the disaster.The resilience can be used not only to evaluate the seismic capacity of bridge traffic network before the earthquake,but also to predict the function recovery of bridge traffic system after the earthquake,so as to provide guidance for disaster relief and reconstruction work.Therefore,it is of great scientific significance and engineering value to carry out the resilience research of urban bridge traffic network system to comprehensively evaluate the seismic capacity of bridge network,traffic flow recovery and disaster relief decision.Based on the analytic hierarchy process(AHP),the weight of the components in the single bridge is determined,and the resilience of the single bridge is obtained by using the fuzzy comprehensive evaluation method and the AHP.Then,the Actual area bridge traffic network model is selected,the theory of vulnerability,post-earthquake recovery process and traffic flow distribution is combined to realize the quantitative analysis of the resilience of bridge traffic network,the main research content is as follows:(1)Based on the analytic hierarchy process(AHP),the weighting of bridge components is studied,and the basic data is obtained by expert questionnaire.The quantitative evaluation of damage degree of bridge members is deduced by fuzzy comprehensive evaluation method to obtain the percentage of residual function of bridge.Based on bridge repair time model,establish a link between resilience metrics and repair time.(2)Based on the bridge traffic network model of HAZUS,the road traffic capacity is calculated and the road impedance function is calculated at each time point.Based on the theory of graph and non-equilibrium distribution,the traffic distribution characteristics of traffic points at different time points after the earthquake and the total time of network traffic are studied.(3)Using the control variable method,the post-earthquake demand matrix and the basic capacity of the road unchanged as the goal.The influence of the ratio of bridge function lifting on the total time of bridge network is studied.The method of determining the optimal repair order of bridge in post-earthquake bridge network is proposed,which provides the scheme and reference for earthquake relief and reconstruction decision...