Rail residual stress distributions can be complex and variable in nature, as different manufacturing techniques produce varying stress magnitudes and distributions. To evaluate the effect of residual stresses on rail integrity, an analysis technique was sought that could quantify the effect of these stresses on web crack propagation.
The computer program LS-DYNA3D was used to simulate the behavior of a specific, though representative, heavy truck cab-over tractor-trailer vehicle during a full 180° rollover event. These simulations provide a key component in the development of a physical testing procedure for evaluating structural integrity and occupant crash protection system designs in heavy trucks.
The United States Food & Drug Administration (FDA) requirements for Class III implantable medical devices requires a 10 year life, or approximately 400 million cycles of service.