Until now,seismic-isolation structures have not yet been applied in the railway field.The reason is that though a seismic-isolation structure can reduce the inertial force to the structure,the energy absorption causes...Until now,seismic-isolation structures have not yet been applied in the railway field.The reason is that though a seismic-isolation structure can reduce the inertial force to the structure,the energy absorption causes big response displacement on the structure,which adversely effects the running safety of the trains supported by the structure.In this paper,a methodology for seismic running safety assessment is introduced,and a new type of seismic-isolation foundation is proposed,which can convert the seismic response displacement in the lateral direction of track to the longitudinal direction that has a less adverse effect on the running safety of the train.The isolation foundation is composed of FPS(Friction Pendulum System)slider,concave plate and guide ditch.Moreover,through model experiments and 3D numerical simulation,it is verified that the proposed foundation can keep both the effects of the seismic isolation and the running safety of the train during an earthquake.展开更多
A method for reducing the damage to a structure caused by an earthquake namely,using laminated rubber for seismic isolation is proposed,and the vibration characteristics of the rubber(which minimizes the seismic respo...A method for reducing the damage to a structure caused by an earthquake namely,using laminated rubber for seismic isolation is proposed,and the vibration characteristics of the rubber(which minimizes the seismic response of the structure during an earthquake)is optimized.A method called“Equivalent Linear System using Restoring Force Model of Power Function Type”(PFT-ELS)is applied to nonlinear vibration analysis of the rubber.In that analysis,a building with 15 layers of the laminated rubber is modeled.The seismic response of the building is analyzed,and the usefulness of the laminated rubber is demonstrated by comparing the seismic responses in the cases with and without the laminated rubber.In addition,the hysteresis restoring-force characteristic of the laminated rubber,which minimizes the seismic response of the building,was optimized by using a genetic algorithm(GA).Based on these results,the optimum restoring-force characteristic for different earthquakes was determined.As a result,it was clarified that the developed optimization method can determine the vibration characteristics of the laminated rubber for minimizing the damage to the structure in the design phase.展开更多
文摘Until now,seismic-isolation structures have not yet been applied in the railway field.The reason is that though a seismic-isolation structure can reduce the inertial force to the structure,the energy absorption causes big response displacement on the structure,which adversely effects the running safety of the trains supported by the structure.In this paper,a methodology for seismic running safety assessment is introduced,and a new type of seismic-isolation foundation is proposed,which can convert the seismic response displacement in the lateral direction of track to the longitudinal direction that has a less adverse effect on the running safety of the train.The isolation foundation is composed of FPS(Friction Pendulum System)slider,concave plate and guide ditch.Moreover,through model experiments and 3D numerical simulation,it is verified that the proposed foundation can keep both the effects of the seismic isolation and the running safety of the train during an earthquake.
文摘A method for reducing the damage to a structure caused by an earthquake namely,using laminated rubber for seismic isolation is proposed,and the vibration characteristics of the rubber(which minimizes the seismic response of the structure during an earthquake)is optimized.A method called“Equivalent Linear System using Restoring Force Model of Power Function Type”(PFT-ELS)is applied to nonlinear vibration analysis of the rubber.In that analysis,a building with 15 layers of the laminated rubber is modeled.The seismic response of the building is analyzed,and the usefulness of the laminated rubber is demonstrated by comparing the seismic responses in the cases with and without the laminated rubber.In addition,the hysteresis restoring-force characteristic of the laminated rubber,which minimizes the seismic response of the building,was optimized by using a genetic algorithm(GA).Based on these results,the optimum restoring-force characteristic for different earthquakes was determined.As a result,it was clarified that the developed optimization method can determine the vibration characteristics of the laminated rubber for minimizing the damage to the structure in the design phase.
