Dynamic Analysis Of Deep-Water High Pier Bridge Under High-speed Train

With the rapid development of the world’s high-speed railway, the dynamic vibration problem between the train and the bridge has been subject to great attention. The high-speed trains would impact the bridge vibration, thus affecting the the working-state and the life of the bridge. At the same time it will affect the stability and security of train when it is working. With the continuous development of the railway system, it is inevitable that we must construct a lot of high-pier bridge because of the complexity of China’s topography.It also brought many problems on the project for the construction of the bridge. So study the dynamic response problem of the deep-wate-high-pier bridges under the action of the high-speed trains have very far-reaching significance.Research on the basis of the domestic and foreign high-pier bridge, axle coupling dynamics theory and methods, water and structural dynamic interaction theory. Using Midas which is bridge finite element analysis software to establish train and bridge and deep-water-pier system dynamics model and simulate the actual vibration state of deep water pier bridge under the action of the train.And studied the affect of continuous rigid frame bridge under the action of the high-speed trains.And the water to impact of the bridge dynamic response. And there are analysis and discussion as following:(1) Using the Midas finite element software to establish a continuous rigid frame bridge finite element model, and analyzed static characteristics and dynamic characteristics of the bridge.(2) Compared the bridge static analysis results with dynamic time history analysis results and later is lager than before. And with increasing speed, the dynamic response is also growing significantly.(3) Using the Midas finite element software, simulating high pier bridges at different depths and calculated the natural frequencies of bridges. Continuous rigid frame bridge natural vibration frequency in the water is lower than frequency at none water.With the pier depth increasing in water, the bridge’s natural frequency decreases. (4) Taking into account at the different water depth and the same as moving loads, the dynamic response of bridge mid-span and the pier top are studied. With increasing water depth, the maximum displacement, velocity and acceleration of bridge mid-span(or pier top) are decreased. Because of water, the pier vibration is interference by the water, the vibration displacement, speed, and acceleration of the pier have been limited, which affects the vibration characteristics of whole bridge structures.