Note: This article presents the Joint Closure Temperature (JCT) for free thermal expansion (FTE) track superstructure ; it is directly related and should be read in conjunction with the following articles: When can a rail be called long? presenting the definition of the concepts long rail and short rail, from thermal behaviour perspective. Track longitudinal resistance presenting the two…
All the railway track fishplates for mechanical joints are designed to provide a gap to the rail web. This gap, together with the wedge shape of the fishplate section ensure, by tightening the joint bolts, the correct alignment of the rail head between the two jointed rails. The bolt tightening torque is developing in the bolt a…
Thermal expansion When exposed to temperature variations, the rail tends to vary its length. If this tendency is freely allowed, for a temperature variance Δt°, the rail length L will vary by ΔL. This length variance can be computed as: ΔL = αLΔt° In this formula, α is the steel expansion coefficient = 11.5·10−6 mm/mm°C. If…
A rail joint is a track component that connects two pieces of rail and it provides room for rail expansion and contraction due to the changes in temperature. The mechanical rail joint is designed to allow a gap variation and, as such, has two well defined limits of this gap. The minimum gap of a mechanical rail…
The track buckling happens in hot weather because of a multitude of factors but it is massively influenced by the track longitudinal and lateral resistances. Both these resistances have three levels of action: Figure 1. The three levels of track lateral and longitudinal resistance – between rail and fastening – at this level all the modern fastenings are behaving…
In 2005-2006 at the Technical University of Civil Engineering Bucharest was designed for SUDAREC a special insulated scarf joint (IBJ), to be installed and used on the Romanian railway sections of the Fourth Pan-European Corridor. The project included: – geometrical design of all the joint elements for 4 types of rail and 3 sectioning angles
A railway track blog 