Results of a Comparative Damage Detection Case Study

A significant amount of attention has been devoted to rapid bridge testing in recent years at the Institute of Theoretical and Applied Mechanics.New methods, such as the Vehicle Scanning Method and Moving Impulse Load Testing, have been developed and/or tested on a scaled laboratory bridge model.This article summarizes all conducted tests, discusses the evaluation methods used, presents the results obtained, and explores possibilities for their improvement.Among the tested methods, the application of Moving Impulse Load (MIL) moving at slow speed, with an excitation frequency around the first natural frequency of the tested bridge, appears to be the most promising.Two passages of the MIL allow for an approximate estimation of the dominant natural frequencies, while repeated passages at small velocity increments provide an excellent means of detecting changes in structural stiffness.