Research On Damage Identification Of Bridge Based On Curvature Mode And Wavelet Analysis

In order to identify the local bridge damage, this article from the perspective of starting modal analysis, modal curvature is the basis and select wavelet analysis as a means. Wavelet transform is sensitive to the mutant signal, identify damage localization and quantification based on wavelet transform coefficient that curvature mode decomposed by wavelet transformation.This article briefly describes the curvature mode theory, through the simple beam is simulated numerically with the help of ANSYS, we obtained that curvature mode can not effectively identify the small damage of structure. The curvature mode indicator has limitations as an injury determination. But the theory which stiffness of the damaged area reduced causing the curvature changes is feasible. So take advantage of wavelet analysis, using wavelet "Math magnifying glass" to further tap the utility feature information of curvature mode.In order to verify the effect of damage identification method of curvature mode based on wavelet analysis to conduct numerical simulation. Making curvature modal studied by multi scale analysis, we obtained that wavelet coefficients damage nearby produce mutations. It can well discriminate the damage location. The simple beam is simulated numerically, and its curvature mode are analyzed by wavelet transform, from the logarithm of which Lipschitz exponent curve is obtained, conclusion is that there is a corresponding relationship between the Lipschitz index and the extent of damage. And using the method of extension curvature mode signal proposed identify the end of beam damage.At last the single box single room footbridge is damage simulated damage numerically; obtained satisfactory recognition effect, further proof the theoretical and practical value of method.