Why a right hand curve is positive?

In transportation engineering there is the following signage convention  for curves in horizontal alignment design: a right hand curve is considered positive a left hand curve is considered negative This convention is considered relative to the stationing direction of that alignment. This signage convention is established in the following way (see the figure above):

Virtual Transition

This is an animation showing how a PWay Track Horizontal Alignment Virtual Transition is defined by the trajectory of the vehicle centre, when is passing over a railway track section with a sudden change in curvature: The nature of this curve is presented in this post: THE VIRTUAL TRANSITION CURVATURE VARIATION. More details about this principle…

Buckling prevention

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…

Cant and Cant Deficiency. Where is the 11.82 coming from?

A railway vehicle moving along a circular curve is subjected to an inertial centrifugal acceleration (ac), directly proportional with its speed and in reverse proportion with the curve radius. This lateral acceleration is perceived by the passengers as an uncomfortable sensation and, above a certain limit, endangers the lateral stability of the running vehicle. In…

The limits of the track alignment design parameters

(A commented extract from BSEN 13803-1 (2010) Railway Applications – Track – Track alignment parameters – Track gauges 1435 and wider – Part 1: Plain Line) The track alignment design PARAMETERS (BSEN 13803-1 – 5.1.2) In the design process the values of the track alignment parameters are chosen to ensure a safe riding with at least…

Reinforced Scarf Joint – JIL ESSO

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