The Seismic Responses Analysis Of Space Twisted Cable Planes Single Tower Cable-stayed Bridge

With the continuous improvement of the quality of life there are a growing amount of demand on the landscape of the bridges, therefore, bridge design gurus are searching for the breakthrough on the design and aesthetic of cable-stayed bridge, at the same time, the level of cable-stayed bridge design and construction technology continues to progress in recent decades, making a formal cable-stayed bridge more special-space twisted cable planes single tower cable-stayed bridge come into being. This type of bridge to meet the function of normal bridge, which is more beautiful compared with ordinary cable-stayed bridge and suitable as a city landmark, thus, drawing increasingly attention and use. Nowadays, domestic and international research for this bridge type is not mature enough, however, this type of long-span bridges are generally with huge investment and playing vital roles in transportation, having significant impacts on the national economy and people’s lives and property. It is very necessary to ensure those bridges safe in the earthquake, and thus their seismic response analyses are very important.In this paper, taking Sanwei Road Cross-Luan River Bridge (hereinafter referred to as the "Sanwei Road Bridge") as the background to study the dynamic characteristics and seismic response of the space twisted cable plane single tower cable-stayed bridge. The main contents include the following sections:(1) The development of the history of cable-stayed bridge and the current development of Chinese space twisted cable planes single tower cable-stayed bridge have been introduced. Taking Sanwei Road Bridge as the engineering background to establish the finite element model of the space for the dynamic analysis, summarizing some bridge vibration characteristics of the space twisted cable planes single tower cable-stayed bridge, and provide as the basis for future dynamic calculation.(2) Using the response spectrum method to analyse Sanwei Road Bridge seismic response, carried out the seismic longitudinal, horizontal, vertical input, and consider a combination of longitudinal and vertical input.(3) The displacement and the internal force response peak in the longitudinal, horizontal, vertical and combination of longitudinal and vertical incentives can be known by the time history analysis of Sanwei Road Bridge and compare the results.(4) Comparing the result of response spectrum analysis with the conterparts of time history analysis indicate that the two results are very close and can be used as the basis for seismic design. Checking through the analysis of the peak response of displacements and internal forces, seismic forces do not control the bridge design.The law obtained from this paper can be used as a basis of seismic design for the type of bridge and regarded as reference for seismic response analysis of other similar bridges as well.