Comparative study of the seismic performance of prefabricated and cast-in-place subway station structures by shaking table test

Abstract

With the design and development of the first fully prefabricated subway station structure (assembled structure) in Changchun, China as the engineering background, large-scale shaking table tests were carried out on the new single-arch and long-span assembled structure and the traditional cast-in-place subway station structure (cast-in-place structure). Based on the seismic response of the cast-in-place structure, the seismic performance of the assembled structure was studied in detail using the comparative analysis method. The variation trend and range of the natural vibration frequency and damping ratio of the two structure model systems were basically the same; the surface settlement of the assembled structure model was 0.7 cm less than the cast-in-place structure and the damage of the assembled structure was more serious. The graded evaluation comparison of the video surveillance showed that the integrity and rigidity of the cast-in-place structure were better than those of the assembled structure. The comparative analysis of seismic response between model soil and model structure showed that the seismic energy absorption performance of the assembled structure was better but the deformation resistance performance was slightly lower than the cast-in-place structure. Under E2 and E3 earthquakes, the damage and deformation of the assembled structure were still in a safe and controllable small range. It was predicted that in the case of an ultimate earthquake (≫ E3), the prefabricated subway station structure would degenerate into a three-hinged arch mechanism to maintain relative stability, and it was not easy to cause an overall collapse and other serious damage situations compared with the traditional cast-in-place structure. The comparative analysis of the performances of the two structure types in shaking table tests showed that the seismic performance indexes of the single-arch and long-span prefabricated subway station structure met the design requirements.