Damage Detection Using Improved Direct Stiffness Calculations — A Case Study

The improved direct stiffness calculation (DSC) is a simple and relatively practical technique to estimate the bending stiffness along beam-type structures based on modal parameters and thus to assess damage in the structure. Application of this technique to a real continuous bridge, named Truckee River Bridge (TRB) in California, is presented in this paper. Comparing the stiffness estimated from baseline condition with that obtained from different damage scenarios in consideration of measurement errors, the damage location and its severity were reliably estimated. Moreover, the improved DSC technique is extended to detect the damage with material nonlinearity, which is simulated with pushover and time-history analyses using one earthquake event. The results of this case study show that the DSC is valid and efficient for identifying the damage with material nonlinearity in beam-type bridges using low-order mode shapes, which is advantageous for in-suit structural health monitoring applications.