Research On Coincidence Setting Of Horizontal And Vertical Curves Of Passenger And Freight Railways Based On Dynamic Simulation

With the rapid development of China’s railway industry,the passenger and freight railway is one of the major railway lines in China,which mileage of construction and operation is in continuous growth.In China,the alignment design specifications don’t allow the vertical curve to coincide with the transition curve.This brings a lot of inconvenience to the railway line design,will also increase the difficulty of line selection in difficult locations and the economic investment in construction.In addition,with the improving of technical standards for the laying,maintenance and repair of railway,which can meet the requirements for the laying of complex space lines when the vertical curve and the transition curve are coincidentally set,and the maintenance requirements for the linear maintenance in the process of operation.Therefore,it is necessary to research the line of coincidence between the vertical curve and the transition curve of the passenger-freight railway,in order to design the railway line flexibly and reduce construction investment.A multi-body dynamics software SIMPACK was used to respectively establish passenger and freight vehicle models.According to the speed matching of the passenger and cargo vehicles in the specification Code for Design of Railway Line,the selection of 160/90,200/120km/h speed matching for the coincidence setting of the vertical curve and the transition curve was studied.First of all,the influence of vertical curve type on the dynamic response of the vehicle was studied by respectively setting the concave and convex vertical curves to coincide with the transition curve.Secondly,the change regulation of the dynamic responses of vehicles with two vertical curves under the two types of vertical curves was studied to determine the most unfavorable coincidence positions for the two types of vertical curves.Thirdly,by studying the regulation about dynamic response of the vehicle with radius and superelevation variation when the vertical curve and transition curve were set to coincide at the corresponding unfavorable position,and the parameter setting method was orthogonal test during the research.Finally,whether the vertical curve and the transition curve can be set coincidently in the various matching conditions were analyzed,by comparing the dynamic response values with allowable values of the passenger and freight vehicle’s safety and the passenger’s comfort in relevant specification.The feasible coincidence position and the matching of the radius and the superelevation were determined.The paper concludes that the dynamic response of the vehicle changes with the coincident position,radius,and superelevation about these two types of speed matching and two types of vertical curves,based on simulation analysis.It is determined that both types of vertical curves can be coincidently set at any position of the transition curve under the matching of the alignment parameters specified in the specification.In addition,the feasible matching values of radius and superelevation that can be set to overlap the vertical curve and the transition curve are determined.