Single Steel Tower Cable-stayed Bridge Seismic Response Analysis

Cable-stayed bridge as one of the modern bridge structure form has the very big development space. No matter from the aspects of structure or building materials are continuously toward a more beautiful, practical, light in the direction of the development, also, it becomes to a large span and complex structure form. So research on this kind of bridge’s seismic response is one of the bridge engineering’s concerns. Panjin Liandao East Bridge is a335m total span cable-stayed bridge what has double space steel cable pane, main span using orthotropic bridge panel, side span using steel girder type steel box girder and the tower is similar to a swan’s "head"&"neck" space structure. It has very important significance for analyzing the seismic response, cause of its unique modeling, complex system structure, the site’s importance, the influence on national economy and human life and property. This article will be research on the bridge’s dynamic characteristics and seismic response in a systematical way.Firstly reviewed the development of cable-stayed bridge, and the characteristics of the single pylon cable-stayed bridge, introduced the related content of bridge seismic damage and some methods of Bridges in seismic response analysis as the basis of theoretical analysis below.The author using Midas/Civil software to simulate all the parts in accordance with the relevant specification to set up a finite element model of East Bridge, considering interaction of foundation and structure. To understand the vibration characteristics of this bridge, the author according to the theory of modal analysis of finite element calculation of dynamic characteristics and analyzing the main order vibration modal.On the basis of modal analysis, to analyze structure response spectrum according to the geological data and in accordance with the norms standard response spectrum curve. And te contrast the values through considering the vertical and horizontal as common input on structural response and only considering the horizontal input influence.Introduce the basic theory of dynamic time history analysis and how to select the seismic wave. Come up with the internal force and peak value under the action of one-way and combination incentive by using the dynamic time history analysis method. Comprise the results between the response spectrum and time history analysis eventually.The conclusion summarizes what the paper did, and points out some problems need to be solved. Hope that it can provide some advisable references to the seismic analysis of other similar bridges throuth this article research conclusion.