Comparison of the Differences in Impact Factor according to Loading Conditions in the Evaluation of Load Carrying Capacity of a High-speed Railway PSC BOX Girder Bridge

Abstract

In this study, the load carrying capacity was evaluated using the results of the dynamic load test, instead of the static load test of the field, in the precision safety diagnosis of a high-speed railway PSC BOX girder bridge, and the differences in the impact factor of the bridge according to the load condition of the train and the configuration of the bridge were compared. The impact factor of the bridge was obtained from the measured displacement response via static and dynamic tests for the precision safety diagnosis performed on high-speed railway bridges. The analysis conditions included the location of the sensor, running track of the train, type and span of the bridge, and load condition of the dynamic load test train, test running train, and service train. Consequently, when the impact factor was calculated based on the displacement response of the test running train, instead of the static load test in the load capacity evaluation of the bridge, a difference of -4.96-5.93% was obtained in comparison with the calculation based on the displacement response of the static load test; this corresponds to 0.943-1.053 times the basic load-carrying capacity rate, indicating a difference from the load-carrying capacity rate obtained by the static load test.