A Comprehensive Fuzzy Method in Seismic Disaster Prediction of Urban Rail Transit Girder Bridges

摘要

Based on the earthquake disaster investigation of 123 reinforced concrete girder bridges, altogether eight factors that were the building year, seismic fortification intensity, soil site category, failure extent of ground soil, superstructure of bridge, constructional measures for seismic resistance, heights of the piers and abutments, and the bridge spans, those affecting the seismic performance of bridges were considered in the seismic disaster prediction. According to the principle of maximum degree of membership, the fuzzy evaluation subsets for the different influential factors were determined by empirical statistic method. The corresponding weight coefficients were presented based on the statistical analysis of the seismic damage of 123 existing bridges. Relying on the developed prediction model, a Fortran based calculating program was developed to predicting the seismic disasters of the girder bridges in urban rail transit. It was shown that the method proposed in this paper was feasible through the comparing analysis of the actual seismic damages of the 123 existing bridges. The Fortran program could be planted to the existing GIS system to predict the arbitrary girder bridge in urban rail transit.