Study On The Damped Energy-dissipated Earthquake-reduction Technique Of Self-anchored Suspension Bridges

The earthquake response and fortification are very complex to Long-span Bridges. The Suspension Long-span Bridges are moreover the hinge of transportation and have important influence on national economy. Once destroyed, it will lead to huge economic lose. So it is very important to adopt the effective seismic fortification measures to the bridges. By taking ShaoJia Channel Self-anchored Suspension Bridge as an example, this paper presents the energy-dissipated and earthquake-reduction technique and theory base of Long-span Suspension Bridge.First literature of results and progress on energy-dissipated and earthquake- reduction technique of Bridge is reviewed. Then numerical simulation is applied to study several energy- dissipated and earthquake-reduction devices as follows.1. According to the structure characteristic of Self-anchored Suspension Bridge, the computing theory has been analyzed and equilibrium state of cable system and whole structure have been clarified. The reasonable finite element model has been established and the structure dynamical characteristic has been analyzed. Then this paper has considered two types of transverse boundary conditions, that is, the transverse boundary condition between the girder and the transition piers is free or fixed.It is shown that the value of longitudinal displacement of deck and the internal force at the bottom of tower are relatively big on these two types of boundary conditions because the structure is float system. So the longitudinal damper settings should be taken into account to control the longitudinal displacement of deck and the internal force at the bottom of tower. If the transverse boundary condition between the girder and piers is fixed, the transverse displacement of deck can be controled, but the value of internal force at the bottom of piers is relatively big. So the transverse damper settings should be taken into account to control the internal force at the bottom of piers. if the transversal damper settings are not be considered, the fixed transverse boundary condition between the girder and piers is recommended.2. The earthquake-reduction mechanism and disposal scheme of viscous damper have been analyzed. The law how to choice damp exponent and how to choice coefficient...