AN EXPERIMENTAL-STUDY OF STATIC AND DYNAMIC-RESPONSES OF PRESTRESSED CONCRETE BOX GIRDER BRIDGES

Experimental data from static and dynamic tests on 1/7-scale direct models of simply supported, one- and two-cell, box girder bridges are presented. Variation of flexural and torsional stiffnesses and dynamic characteristics, such as the natural frequency of vibrations and damping ratios of the bridge models at different levels of cracking damage, are examined; in turn, these dynamic characteristics can be used to estimate the cracking damage in the bridge. The physical model proved to be an adequate tool for the study of static and dynamic responses of box girder bridges at all load levels.