Bearing Capacity Analysis And Structural Optimization Design Of Light Rail Turnouts Beam

Turnout is the rail of vehicles，and the function is to guide and stabilizevehicles.It has to withstand the impact of a variety of complex loading conditions, andis also the main load-bearing device of vehicles running load. Turnout is the criticalequipment related to the entire rail system whether can be normal and secure.So railturnouts structure should be safe and reliable.It should be adapted to the safe operationof trains. In this paper，we choose the number three light rail turnouts beam whichproducted by East Sichuan Shipyard for Chongqing Rail Transit Co.,LTD.It is abox-shaped structure made by steel.Before being put into use,the bearing capacityneeds to be analyzed and to ensure the feasibility and safety of the product.How toreduce the weight of the beam turnout，reduce production costs and ensure the safetyand reliability of the train is the primary problem.After understanding the structural properties of turnout beam and mastering theoptimization theory，we first introduce the basic principles of structural optimizationdesign and analyse the methods of turnout beam. Establishing a turnout beam finiteelement model by using finite element analysis software ANSYS，then making staticanalysis under various conditions for the force of beam，accurately calculating thestress on the various parts of the track beam，analyzing the maximum stress of railbeam structural deformation on both ends and the middle，to identify areas of stressconcentration.Secondly，we make geometry cleanup and simplify the connection method，mesh，make the definition of design variables，create constraints and responses，buildoptimization models，and make size optimization,topology optimization and shapeoptimization of the beam respectively.These are all depends on HyperWorks.Depending on the size optimization results, we adjust the thickness of the member,effectively reducing the weight of the structure, the weight fell by15.5%. According tothe results of topology optimization to find the optimal distribution of the beammaterial, remove some elements, and partitions are redesigned,the internal componentsof the beam to be adjusted to arrive at a best solution to reduce structural weight by18.4%. By the shape optimizing,the cross-sectional dimensions of the beam were adjusted. The weight of structure decreased by2.63%.Finally，for the results of optimization programs,we find that these there solutionscan meet its strength and bearing capacity requirements of the premise after comparingthe previous optimization results of stress and displacement with back optimizationresults by using HyperWorks. The weight decrease obviously. The results show thatoptimization is obvious and reasonable.We can make full use of the materials andreduce the amount of steel or the quality of the entire beam in order to achieve the beststate.As the same time, it meets the premise of saving the material, reducing theproduction cycle time and cost to achieve the economic and practical purposes.It alsoprovides a theoretical foundation for the re-design of the beam turnouts laid inengineering practice, economic benefits is obvious. The project can be used as areference design.It is significant for the lightweight design for rail transportation.