A crossing is designated either by the angle the gauge faces make with each other or, more commonly, by the number of the crossing, represented by N.

**Number and Angle of Crossing**

A crossing is designated either
by the angle the gauge faces make with each other or, more commonly, by the
number of the crossing, represented by *N*. There are three methods of
measuring the number of a crossing, and the value of *N* also depends upon
the method adopted. All these methods are illustrated in Fig. 14.10.

**Centre
line method**

This
method is used in Britain and the USA. In this method, *N* is measured
along the centre line of the crossing.

**Fig.
14.10 **Different
methods of measuring number (*N*) and angle of crossing

**Right angle method**

This
method is used on Indian Railways. In this method, *N* is measured along
the base of a right-angled triangle. This method is also called *Coles method*.

**Isosceles triangle method**

In this
method, *N* is taken as one of the equal sides of an isosceles triangle.

The right angle method used by
Indian Railways, in which *N* is the cotangent of the angle formed by two
gauge faces, gives the smallest angle for the same value of *N*.

To determine the number of a
crossing (*N*) on site, the point where the offset gauge face of the
turnout track is 1 m is marked. The distance of this point (in metres) from the
theoretical nose of crossing gives *N*.

Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail

Civil : Railway Airport Harbour Engineering : Railway Engineering : Points and Crossings : Number and Angle of Railway Crossing |

**Related Topics **

Privacy Policy, Terms and Conditions, DMCA Policy and Compliant

Copyright © 2018-2024 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.