Seismic Fragility Analysis Of Urban Road Network Based On Monte Carlo Simulation

The urban road network is an important lifeline engineering system and a basic engineering facility system that maintains modern urban transportation functions and regional economic functions.Its earthquake resistance directly affects whether the city's emergency rescue and disaster relief transportation can be carried out quickly after the earthquake.Based on this,two-dimensional spatial network statistical eigenvalues are used as damage evaluation indicators,and a class of urban road network seismic fragility evaluation methods is proposed.The Monte Carlo simulation method is used to calculate the seismic fragility matrix and fragility curve.The main contents include:First,the urban road is abstracted as a planar network,and a method for modeling the urban road network using the weighted adjacency matrix is given;the evolutionary power spectrum based on the spectral representation method and the time-varying coherence function model are used to simulate the spatially varying ground motion at the urban scale.After that,the steps of the urban road network earthquake damage simulation are given.The post-earthquake impassability probability of each road segment is calculated according to the road fragility function,and the Monte Carlo simulation method is used to simulate the whole road network earthquake damage.The urban road systems of Qinhuangdao City and Tangshan City in Hebei Province were selected for network modeling to simulate and analyze the earthquake damage of the road network under different earthquakes.Finally,the damage situation of the road network under the action of earthquake is counted.The number of network branches and the maximum branch diameter are used as indicators for evaluating the damage of the road network.,The seismic fragility matrix and the fragility curve of the urban road network are calculated,and the method of the urban road network seismic fragility analysis is given.The seismic fragility analysis method developed for urban road networks in this paper can be used to evaluate the seismic performance of urban road networks and the ability to maintain transportation after an earthquake,and provide a reasonable reference for urban road disaster prevention planning and design.