If L_{1} and L_{2} are actual and theoretical lengths of a tongue rail, d is heel divergence and t is thickness of tongue rail at toe, the switch angle α is

If D is distance between centres of two parallel track of gauge G, then, total length of cross-over (from the point of commencement to the point of termination) with an intermediate straight portion and N crossing, is given by

If a 0.7% upgrade meets a 0.65% downgrade at a summit and the permissible rate of change of grade per chain length is 0.10%, the length of the vertical curve, is