Permanent way detail: What rail top inclination (cant) is provided on the seating of steel sleepers to match the rail's standard inward cant?

Introduction / Context:
Rails are commonly installed with a small inward inclination (cant) so that the rail head aligns optimally with wheel conicity, reducing flange and tread wear. Sleeper seats are therefore prepared to provide this cant consistently along the track.

Given Data / Assumptions:

• Standard track with coned wheel treads.
• Steel sleepers with machined or formed rail seats.
• Standard rail cant practice adopted.

Concept / Approach:
The conventional rail cant is 1 in 20 inward, meaning the rail top is tilted toward the track centerline. Steel sleeper seats mirror this cant to ensure the rail head presents the correct angle to approaching wheels, improving stability, reducing wear, and enhancing riding comfort.

Step-by-Step Solution:
1) Identify standard rail cant = 1 in 20 inward.2) Provide matching cant on steel sleeper seats.3) This maintains uniform geometry and wheel-rail contact conditions.

Verification / Alternative check:
Design drawings and track standards specify a 1 in 20 inward inclination for most mainline track; timber, concrete, and steel sleepers are all configured accordingly.

Why Other Options Are Wrong:

• No cant or outward cant misaligns the rail-wheel interface and increases wear.
• 1 in 40 cant is not the standard value for modern mainline practice.

Common Pitfalls:

• Assuming concrete sleepers alone provide cant; all sleeper types must match the specification.

Final Answer:
Inward cant of 1 in 20.