Abstract：The health status of the in-service bridge structure, related to the safety of people’s lives and property, therefore, it is extremely important to understand their damage status. At present, the damage identification usually has to suspend the operation of the in-service bridge, causing a huge economic impact. In order to solve this problem, the paper presents a in-service bridge damage location identification method without interrupting the operation of in-service bridge. Curvature mode method is an ideal method to identify the structural local damage, with d advantage of easy to operate and sensitive to damage location, while the frequency is easy to test with high precision. An improved structural damage identification method is presented, based the change rate of structural curvature and frequency. In order to solve the problem that inspecting works always interrupt the operation of the in-service bridge, the stochastic subspace identification method is introduced in the method. Finally, the combination method presented herein is verified by a simple support steel beam tested in the laboratory. The test results show that the improved combination index method can effectively identify the bridge damage location without interrupting the in-service bridge operation.
2011, Vol. 30 
