Analysis Of Seismic Of The Tower Long-Span Cable-Stayed Steel Truss Bridge

It is well known, in general, that the long-span cable-stayed bridge is the hinge of transportation, which is heavily invested in,used frequently and has important Influence on national economy.Once destroyed,it will cause huge economic lose and heavily influence earthquake disaster reduction and repair of disaster area which damaged in an earthquake.How to improve the earthquake resistance ability of bridges is although an important subject for research as well as the target for pursuing. Therefore it is very important to adopt the correct and effective earthquake reduction design to make sure the safety of the structure under earthquake.In making shock earthquake reduction design of cable-stayed bridge, the leading thinking is that,in the earthquake,the internal force and displacement of the cable-stayed bridge are the smaller the better. However,traditionally,if a cable-stayed bridge was designed without any effective seismic fortification measures,small internal force always accord with great displacement, and vice versa.In this paper, a tower span rail-cum-stayed steel truss bridge research background, finite element program MIDAS/Civil establish a computational model without damping measures and the use of different parameters of the viscous dampers and dynamic characteristics analysis, analysis of viscous dampers on the dynamic characteristics. Use the response spectrum method under the most unfavorable earthquake probability of exceedance in10%of the full bridge without damping measures in100years, the analysis of the main truss vertical bending, the longitudinal vibration of the system, two main towers reverse scoliosis, with two main tower calculate its dynamic performance and seismic response to the dynamic characteristics of the scoliosis completed bridge. Especially for the above modal structure of key parts of the pier top, the bottom of the pier, cap the end of the main tower of the main six key section of the position of the calculated one by one. On this basis, full-bridge internal force influence the modal analysis of internal forces to control cross-section of the main tower and auxiliary pier side pier.History analysis method in the case of damping measures impact on the full-bridge modes (modes involved in quality factor greater than or equal to0.01%of the vibration), the use of seismic response of the concept of a reduced rate, respectively, load cases in accordance with a total of99kinds of different seismic parameters to analyze the sensitivity of its parameters.Achieved through the analysis on the the viscous dampers Bridge model, the Structure Control Section Analysis under the premise does not increase, reducing the maximum displacement response of the control node at the principle of best damper parameters. Provides a reference for this type of bridge seismic damper parameters.