Dynamic Response Modeling of Long Cable Steel Bridge for Structural Health Monitoring

Structural health monitoring is becoming a hot research direction in civil engineering. Considering the importance of long cable steel bridges in local transportation and field economic development, strong attention has been paid to structural health analysis to monitor the integrity, durability and reliability of the bridges. Long cable steel bridges are vulnerable to fatigue damage. Local test method, adopted in a number of fatigue damage analysis for short and/or medium bridge, could not be used for long cable bridge fatigue analysis as long cable bridges have many structural properties making inspection, instrumentation and testing of them very difficult. Finite Element Method (FEM), recommended as a rigorous method for fatigue damage analysis by British Standard, is proposed in this paper to analyze fatigue damage for a practical long cable steel bridge under traffic loadings. To this end, an effective Finite Element (FE) model of the Tsing Ma Bridge (TMB) in Hong Kong, embodying the properties of almost all the structural members is developed. Verification of the efficiencies of the model for bridge modal analysis and bridge dynamic response modeling are presented. The computed results are compared with, and found to match closely, online measured data. It shows the constructed bridge finite element model is efficient for structural health analysis