Bi-directional Loading Hybrid Test of Square Section Steel Piers

Bi-directionalloading test are carried out to examine response behavior of square section steel bridge piers under the prescribed ground accelerations in the Design Specification of Road Bridge in Japan. Each of these ground seismic motions has two horizontal components. Both uni-lateral and bi-lateral excitations are imposed to the 2.4m high pier models with the section of 450mm x 450mm. 1t is found from the test results that the bi-lateral excitation deteriorates the lateral bearing force of the piers compared to the uni-lateral loadin