Windresistant design(2)

[61] Reliability of Train Car Against Cross Winds Considering Uncertainty in Estimated Aerodynamic Force

○Yosuke Nagumo¹, Takeshi Ishihara² (1.Department of Civil Engineering, School of Engineering, The University of Tokyo / East Japan Railway Company, Research and Development Center of JR East Group, Disaster Prevention Research Laboratory, 2.Department of Civil Engineering, School of Engineering, The University of Tokyo )

Keywords:Railway, Wind speed, Overturning, Reliability-based design, Safety index

In order to evaluate impact forces by flying debris through a fluid-structure interaction analysis of the debris motion and surrounding fluid motion, numerical procedures to handle the process of impact are investigated. The objective model problem is that a sphere falling in a still air hits the ground. The impact force is applied to the equation of motion of the sphere. The amount of the impact force is determined by giving the condition that the velocity of the sphere has to be zero at the impact. This procedure is improved to remove unphysical numerical oscillation by subdividing the impact process into multiple fine steps. It is found that the impulse is evaluated in the present procedures. The effect of the mass ratio on the impact process is also investigated.