Failure analysis and design optimization of composite train brake shoe.

摘要

This thesis investigates the crack failure of railroad high friction composite brake shoe manufactured by Anchor Brake Shoe Company and used widely in railroad industry. Significant amount of the brake shoes fail before the estimated life period due to cracks near the center slot for heat dissipation and/or near the end of brake shoe under rejection lug. Finite element method is used to determine the root cause of the failure. Design changes are proposed to improve the fatigue life of brake shoe by reducing stress concentrations. A set of dimensions are chosen as design variables and Response Surface Method (RSM) is implemented to achieve the optimum dimension for new design. New design is analyzed using finite element analysis and compared with the original design for fatigue life, which shows considerable amount of improvement in life span.