Seismic Response Analysis Of High Pier And Long-span Continuous Rigid Frame Bridge

With continuously development of China’s western and the highway to the mountain area, the high pier and long-span continuous rigid frame bridge is always the best preference because of its light appearance, convenient construction and strong spanning capacity. And it becomes the main bridge of highway construction in Chinese Western. However, most of the western region is located in the seismic zone, which provides a higher seismic demand for the design of the bridge. Therefore, to search the seismic behavior of the high pier and long-span continuous rigid frame bridge, after discussing the principle of seismic design and seismic design method, the dynamic performance of the bridge have been analyzed based on practical long-span continuous rigid frame bridge. The response spectrum method and time history analysis method are used to analyze the seismic performance of bridge structure. The basic characteristics and development law of seismic response of high pier and long span continuous rigid frame bridge are obtained. The main research contents and conclusions of the paper are listed as following.1. Based on the basic principle of structure dynamics, the finite element model of structural dynamic analysis is established by using the finite element calculation software Midas/Civil, and the dynamic characteristics of the bridge structure are solved. The difference of vibration characteristics with the consideration and without consideration of pile-soil-structure interaction is comparatively analyzed. The results show that considering pile soil structure interaction of vibration period is greater than that of without considering pile soil structure interaction of natural period of vibration.2. The seismic performance and the key sections of the internal force and deformation is analyzed on based on the commonly used bridge seismic response analysis method, including static method, response spectrum method and time history analysis method, The results show that the main seismic design key is the lower part of the structure of the high pier and long-span continuous rigid frame bridge.3. The fiber model plastic hinge is used to elastic plastic of the bridge, through adjust the input amplitude of the seismic methods, in-depth analysis of various vibration under the condition of plastic hinge positions in the sequence and the failure state, the seismic design method is put forward the need in the potential plastic hinge position through the reasonable reinforcement to increase the whole bridge ductility.In summary, through the analysis of the seismic response of high pier long-span continuous rigid frame bridge, the seismic design methods is obtained, and the measures to improve the ductility performance are put forward. The results of research can provide theoretical support and calculation reference for seismic response analysis and structural safety design of high pier and long span continuous rigid frame bridge.