BRIDGE-PIER SAFETY EVALUATION METHOD USING NONDESTRUCTIVE IMPACT TESTS

초록

This study aims to establish an evaluation method for bridge pier safety. To achieve this aim, a full-scale bridge pier was constructed, and a series of nondestructive tests were conducted using impact loads. The overburden loaded in the full-scale bridge pier was increased from 0 tonf up to 25 tonf by increments of 2.5 tonf. Impacts were applied to the upper and lower parts of the bridge pier in longitudinal, transverse, and lateral directions to analyze the behaviors of the bridge pier. Accelerometers were used to measure acceleration responses to impacts. Test results were converted to natural vibration frequencies according to impact direction and overburden using a fast Fourier transform algorithm. In addition, phase differences were utilized to analyze the behaviors of the bridge pier from the 1st to 4th modes. The effect of scouring was numerically analyzed. Ultimately, the safety of the bridge pier could be reasonably evaluated through the 2nd and 3rd modes.