Research On Aseis Matic Design Of Middle Span Cable-Stayed Bridge

As one of the most devastating natural disaster, earthquake always causes tremendous losses of life and property. In strong earthquake, bridges may go into nonlinear phase, for example, yielding of pier, unseating caused by excessive seismic displacement of bearing, colliding between adjacent structures, etc. In recent years, many researchers have been carry on seismic response of large span cable-stayed bridges, and many useful conclusions have been obtained. At the same time, little research work has been made on the seismic response of middle span cable-stayed bridge, which is far more than the former in quantity. The seismic response analysis of middle span cable-stayed bridge is studied in this dissertation. Some advices on seismic design of cable-stayed bridges are achieved.A typical cable-stayed bridge with middle span has been carefully analyzed in this paper. Through analysis of the effect of high vibration mode and geometric nonlinear on the internal forces of various components, some conclusions on the method to consider those effects when designing cable-stayed bridges have been obtained. Detailed static analysis and seismic response analysis of various structural systems and load cases have also been finished. Combining the results of static and seismic response analysis, the section strength of various components are verified according to the current method used in bridge design. By analysis of the most suitable structural system for static and seismic design, and the relation between the capacity and requirement of components under different seismic levels, the suitable structural system and component sections that should be paid attention to and be strengthened in seismic design are presented. The conclusions obtained in this paper are useful for the design of bridges.The main contents of this paper are described as follows.(1) Effects of high vibration mode on seismic response of various components of middle span cable-stayed bridge.(2) Effects of geometric nonlinear on the internal forces about various...