Requirements for an Ideal Rail Section
- The section of the rail should be such that the load of each wheels is transferred to the sleepers without exceeding the permissible stresses.
- The section of the rail should be able to withstand the lateral forces caused due to fast moving trains.
- The underside of the head and top of the foot of the rail section should be of such aslope that the fishplates fit snugly.
- The center of gravity of the rail section should preferably coincide the center of the height of the rail so that maximum tensile and compressive stresses are nearly equal.
- The web of the rail section should be such that it can safely bear the vertical load without buckling.
- The head of the rail should be sufficiently thick for adequate margin of vertical wear.
- The foot of rail should provide sufficient bearing area on the underlying sleepers so that the compressive stresses on the timber sleeper remain within permissible limits.
- The section of the rails should be such that the ends of two adjacent rails can be efficiently jointed with a pair of fish plates.
- The surfaces for rail table and gauge face should be sufficiently hard to resist the wear.
- The contact area between the rail and wheel flange should be as large as possible to reduce the contact stresses.
- The specimen of rail should be able to withstand the blow of a falling weight in the test specified by the specifications.
- The composition of the steel should conform to the specifications adopted for its manufacture by Open Hearth of Duplex Process.
- The overall height of the rail should be adequate to provide sufficient stiffness and strength as a simply supported beam.
- The stiffness of a rail section depends upon the moment of inertia. The economical design should provide maximum moment of inertia per unit weigh of rail with due regard to other factors.
- The section moduli of the rail section and that of a pair of fish plates should be adequate so as to keep the rail and fish plates within permissible limits.
- The foot of the rail should be wide enough so that the rail is stable against overturning.