![]() ![]() The vibration damping effect and vibration reduction law of suspended structure are discussed at different apparent wave velocity and in the different connection. #Midas civil 2011 full version download series#In order to study the influence of traveling wave effect on the seismic response and damping effect of suspended structure, a series of shaking table tests of the 1 : 20 suspended structure have been carried out to compare and analyze the dynamic responses of suspended structures under two points and a consistent input. ![]() Positive damping effectiveness was commonly achieved from the additional longitudinal viscous dampers under the far-field ground motions when considering the wave passage effect, whereas negative damping effectiveness was observed under the near-field ground motion at certain wave velocities. The wave passage had a great influence on the displacement responses of the towers and the deck and the relative variation amplitudes of the cable forces near the midspan. ![]() The test results show that the damping effectiveness of the additional longitudinal viscous dampers was significantly reduced under near-field ground motion. The seismic responses of the systems with and without viscous dampers, under different types of ground motions considering uniform or traveling wave excitations, were analyzed and compared. A 1/35-scale physical model scaled from a typical long-span cable-stayed bridge was designed, constructed, and tested on four shake tables. This work focused on the damping effectiveness of additional longitudinal viscous dampers employed for seismic control of long-span cable-stayed bridges considering wave passage effects. Finally, some suggestions for further research of the coupling vibration of train–bridge system under external excitations are presented. The characteristics of external excitations, the models of the train–bridge systems under external excitations, and the representative research results are summarized and analyzed. Therefore, this paper provides a comprehensive state-of-the-art review of research works on train–bridge systems under external excitations, which includes crosswinds, waves, collision loads and seismic loads. In these aspects, there is abundant research but lacks a literature review. Therefore, it is of paramount importance to evaluate the safety and comfort of trains when crossing a bridge under external excitations. Meanwhile, frequent extreme disasters, such as strong winds, earthquakes and floods, pose a significant threat to the safety of the train–bridge systems. In recent years, high-speed railways in China have developed very rapidly, and the number and span of the railway bridges are keeping increasing. The effect of steel truss girder stiffness parameter variations on structural internal forces of bridges and the effect of traveling wave effects on structural displacements of bridges in specific apparent wave velocity intervals do not exist universally. The spectral characteristics and the duration of ground shaking have a greater influence on the maximum bending moment values corresponding to the height of the cable tower and the maximum axial force values of the main girder bars corresponding to the length of the bridge under earthquake action. The results show that the displacement of the floating system under seismic action is larger than the other three systems, but its internal force is significantly smaller than the other three systems. The effects of structural parameter variations and traveling wave effects on the seismic response of this steel truss cable-stayed bridge with a single tower and a single cable plane were investigated by the nonlinear time-history analysis method and nonuniform seismic analysis method. The arrangement of the deck type makes the mechanical properties of the cable-stayed bridge more complicated while reducing the cost and increasing the aesthetics. Due to the small self-weight of the steel truss cable-stayed bridge with a single tower and a single cable plane, the torsional stiffness and wind stability of the structure are reduced. ![]()
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