Abstract：Seismic responses of super long-span cable-stayed bridges are highly dependent on the structural systems under strong earthquakes and are also affected by the foundation and site soil. Due to the limitations of facilities and technology of shaking table test, however, few experiments have been carried out on the full model of super long-span cable-stayed bridges up to now. With a trial designed super long-span cable-stayed bridge with main span of 1400m taken as prototype, a full model with pile foundation and site soil was designed with a scale of 1/70. Based on the shaking table array system, the seismic response characteristics of various structural systems under three typical earthquake inputs (including El Centro wave, artificial wave and Mexico City wave) and the influencing mechanism were investigated. The investigated structural systems include the longitudinal semi-floating system, longitudinally and elastically constrained system as well as the proposed energy dissipation system with longitudinal supplementary pier and the proposed transverse energy dissipation system. Furthermore, the seismic performance of different longitudinal structural systems and the control effects of supplemental energy dissipation components attached between the pylons on the transverse seismic response of the cable-stayed bridge were investigated. The experimental results show that: (1) the effect of soil-structure interaction on the seismic response of superstructure shall not be neglected; (2) the effects of higher order modes on the seismic responses of the main tower are evident; (3) the scaled model shall be still in the elastic stage under the actions of El Centro wave and artificial waves with PGA less than 0.4g and Mexico City wave with PGA less than 0.2g; (4) compared with the seismic performance of the floating system, the energy dissipation supplementary pier system on reducing the displacement of the main tower and the relative displacement between tower and girder were superior to those of the elastically constrained system; (5) the supplemental energy dissipation components may obviously reduce the bending moment and strain response of the tower, decentralize the inner force of the tower and dissipate earthquake input energy, but their restraints on the transverse displacement and acceleration of the tower are limited.
谢文 孙利民 . 采用振动台阵的超大跨斜拉桥大比例全模型试验研究[J]. 土木工程学报, 2018, 51(8): 47-59.
Xie Wen Sun Limin . Experimental studies on a large-scale full model of a super long-span cable-stayed bridge by using shaking table array system. 土木工程学报, 2018, 51(8): 47-59.
