Citation

Lockwood C, Thornton PJ. Transp. Res. Rec. 1986; 1071: 48-56.

Copyright

(Copyright © 1986, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

To meet the increased demands imposed on switch and crossing installations by higher train speeds and higher axle loads, British Rail has a continuing program of development work. This program's purposes are to (a) provide junctions for higher speeds and (b) reduce track maintenance costs by improving track layout geometry and component design as well as materials and the support structure. Recent work in these areas includes design of high-speed junctions suitable for speeds up to 125 mph (200 km/hr), and studies of the paths of wheels through junctions, with particular emphasis on entry into switches. Computer simulations have been developed to predict wheel/rail forces. Measurements of actual forces by means of load-measuring wheelsets have confirmed predictions. Theoretical vertical wheel trajectories through a variety of crossings have been considered in detail, leading to proposals for changes in local railhead geometry to reduce impact forces. (Large vertical impact forces measured at crossings are illustrated.) Improved steels have been developed for use in crossings that can be welded into track, thereby eliminating troublesome bolted joints. Better support for switch and crossing work (in the form of prestressed concrete bearers) is being evaluated.

Language: en

Keywords

RAILROAD ROLLING STOCK - Components; RAILROADS