A METHOD FOR FINDING THE CONDITION CHARACTERISTICS OF RAIL TRACKS, AND THE ASSESMENT OF RAIL TRACKS, AND THE EVALUATION OF THE CHARACTERISTICS

摘要

1,271,524. Deriving safe speeds from track condition. F. PLASSER. 25 April, 1969 [25 April, 1968], No. 21167/69. Heading B7N. A method of operating traffic over a railway track at safe speeds comprises the steps of plotting on a graph a curve relating track errors and maximum safe speed whose equation is:- wherein y is the maximum permitted error in mm. for the value x between 0 and 1; f max is maximum permitted track error in mm. for the value x = 0; a is the maximum permitted tolerance in mm. for new or relaid tracks; x = V/Vp, where V is maximum safe speed in km./h. as a function of error y and Vp is the maximum possible speed in km./h. measuring the track errors and deriving from the graph the corresponding values of safe speed and then operating traffic over the track up to said derived safe speed. The Specification describes how the derived values of safe speed are used to define safe speed track stretches and also how a condition index may be obtained by multiplying the length of a track stretch by its maximum safe speed and dividing this by the length multiplied by a theoretical maximum speed.