Static Deformations of Bridges From Quick‐Release Dynamic Experiments

This paper illustrates the application of a new method for performing baseline corrections on accelerograms generated by the quick-release method. These accelerograms are produced when highway bridges are subjected to dynamic excitations by initially deforming the structure and subsequently quick-releasing the loads causing the deformations. In the past, the displacements caused by the quick-release loads have not been recovered because an adequate correction procedure was not available. A baseline-correction method was developed such that the step-function character of the quick-release baseline is preserved. This feature allows the complete static deformation state to be recovered by integrating the accelerograms. The power of the method is demonstrated by applying it to a suite of quick-release data obtained during full-scale field tests of the Meloland Road Overcrossing located near El Centro, California. As a result, complete static deformations of this bridge are obtained as a by-product of the dynamic experiments.