Abstract： Seismic responses of long-span cable-stayed bridges may be significantly affected by the properties of the pile foundation and site soil as well as the spatial effect of ground motion because the long-span cable-stayed bridge has low natural frequencies, structural damping and large spatial scale. However, there are few experimental studies on the full model of a long-span cable-stayed bridge composed of the superstructure, pile foundation and site soil due to the limitations of shaking table testing facilities and technology. A complete model of 1/70-scaled cable-stayed bridge, composed of superstructure, pile foundations and site soil, was designed and fabricated according to a preliminary design of long-span cable-stayed bridge with main span of 1400 m. The full model was tested on the shaking table to study the mechanism associated with the seismic responses of the long-span cable-stayed bridge under uniform and multi-support excitations. Experimental results show that the longitudinal displacement response of the main tower, the longitudinal pile-soil-structure interaction effects of the main tower and piers, and the vertical displacement response of the main span in one side of the full model increase when being subjected to longitudinal multi-support excitations, while the corresponding seismic responses in other side decrease. The transverse displacement response of the main tower and the transverse pile-soil-structure interaction effects of the piers in one side increase when being subjected to transverse multi-support excitations, whereas the corresponding seismic responses in other side reduce. However, the transverse pile-soil-structure interaction effects of the towers and the transverse displacement of the main span in
both sides increase for transverse multi-support excitations. Moreover, it is found that the pile-soil-structure interaction has adverse influences on the acceleration response of the cable-stayed bridge. Therefore, it is suggested that the multi-support excitations and pile-soil-structure interaction should be considered when conducting performance evaluation and seismic analyses on long-span cable-stayed bridges.
谢 文 孙利民 楼梦麟. 多点激励下桩-土-斜拉桥全模型振动台试验研究[J]. 土木工程学报, 2019, 52(5): 79-89.
Xie Wen Sun Limin Lou Menglin. Shaking table test on a pile-soil-cable-stayed bridge full model under multi-support excitations. 土木工程学报, 2019, 52(5): 79-89.
