SOLUTION

Speed-time curve for suburban service

In suburban service, the distance between two adjacent stops for an electric train is lying between 1 and 8 km. In this service, the distance between stops is more than the urban service and smaller than the mainline service. The typical speed—time curve for suburban service is shown in Fig.

The speed-time curve for urban service consists of three distinct periods they are:

(i) Acceleration.

(ii) Coasting.

(iii) Retardation.

For this service, there is no free-running period. The coasting period is comparatively longer since the distance between two stops is more. The braking or retardation period is comparatively small. It requires relatively high values of acceleration and retardation. Typical acceleration and retardation values are Iying between 1.5 and 4 kmph and 3 and 4 kmph, respectively.