Creep:
Creep of rails is the forward movement of rails in the direction of dominant traffic over a period of time. Creep is undesirable because it disturbs the gauge of the track and the position of sleepers.
Creep is adjusted by pulling back the rail after loosening the fish plates and fastenings. Creep can be avoided by providing creep anchors which grip the rail at the sleepers and prevent it from moving forward.
Fastenings
Fastenings are needed to hold the rail firmly on the sleeper. In the case of timber sleepers, the fastening is done by dog spikes or screw spike. In the case of steel sleepers and pre- stressed concrete sleepers clips and rubber pads are used.