Design Optimization of Switch Rails in Railway Turnouts
Other conference contribution, 2012

Inspired by the manufacturing process of switch rails for railway turnouts, a method for the optimization of switch rail profile geometry is presented. The switch rail profile geometry is parameterized with four design variables to define a B-spline curve for the milling tool profile, and two design variables to prescribe the deviation from the nominal vertical path of the milling tool. The optimization problem is formulated as a multi-objective minimization problem with objective functions based on the contact pressure and the energy dissipation in the wheel–rail contact. The front of Pareto optimal solutions is determined by applying a genetic type optimization algorithm. The switch rail profile designs are evaluated by simulations of dynamic train–turnout interaction using a commercial code for multi-body dynamics. The vehicle model is a freight wagon with Y25 bogies and 25 metric tonnes axle load. Traffic is simulated in both travelling directions in the diverging route of a 60E1-760-1:15 turnout. It is concluded that the obtained set of Pareto optimal solutions corresponds to a rather small variation in design variables where increased profile height and increased profile shoulder protuberance are preferred for both objectives.


rail profile






Björn Pålsson


Jens Nielsen


Proceedings of the Contact Mechanics 2012 conference in Chengdu, China.

Areas of Advance


Subject Categories

Applied Mechanics

Vehicle Engineering

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