Re-Engineering Heavy Haul Turnouts for Passenger Higher Speed Rail Operations

With the recent renewed interest in higher speed passenger rail (“HrSR”) in North America, there will be increased pressure on freight railroads to collaborate with public transportation agencies in the establishment of “shared use” tracks. Track infrastructure in these corridors must be robust enough to support the heavy axle loading associated with conventional North American freight traffic while accommodating FRA Class 6-7 passenger operating speeds in excess of 100 mph. Turnouts which permit higher diverging route speeds will become increasingly important as service-sensitive passenger operations look to reduce transit times and freights grapple with capacity concerns. Innovative approaches to the design, manufacture and construction of turnouts are called for. Critical design elements for a new generation of “shared use” turnouts will include: a) Tangential and compound geometries to optimize ride quality and safety; b) Respecting the spatial constraints of existing infrastructure (opposing signal locations) while maximizing diverging route permissible speeds; c) Kinematic gauge optimization through switches to enhance ride quality and increase component life; d) Premium frog designs to minimize running surface discontinuities; e) Cross tie housed rodding and position detection systems to facilitate continuous maintenance surfacing; f) Integrated switch drive, detection and monitoring systems to facilitate proactive intervention by maintenance forces.