Draft:Problem tunnels

Problem tunnels

Problem tunnels Long and steep tunnels can have problems with smoke from steam locomotives and fumes from diesel locomotives. Ventilation and electrification can overcome such problems. If tunnels are too steep then this is a mistake from the designing engineer. Restrictive structure gauges may rule out the use of Garrett locomotives since should the train stall, crew cannot walk past the hot cylinders whether forward or backwards. Example include:

• Wet rails can cause locomotive wheels to slip and the train to stall.

• Wet rails can cause Track circuits to short-circuit so that they always show that track is occupied.

• Curved track makes un-compensated ruling gradient appear steeper.

• Prohibition of certain classes of locomotives.

Examples

• Otford,_New_South_Wales deviated on less steep gradients.
• Ardglen
• Bath, Somerset on Somerset and Dorset Railway
• Cascade old old and new tunnels built with too steep gradients.
• Cascade new old and new tunnels built with too steep gradients.
• Severn Tunnel