The October issue of Trains magazine had two very diverse topics that got me to thinking. The issue was devoted to narrow gauge railroads railroads which had an enormous burst of development beginning almost 149 years ago. That burst was based on false hopes that by underinvesting in infrastructure great results could be obtained cheaply. That bubble created lots of fascinating, if ineffective, railroading. On the other hand the brief technology section at the beginning section of the magazine described revealing test of investment in track structure that was eye opening. Two test segments of slab track (continuous concrete bedded track) were laid at the FRA (Federal Railroad Administration) Transportation Technology Center Inc. near Pueblo. Colorado and set for very high speed tolerances (FRA class 9 for 200 mph operation) (No US trains run this fast or anywhere close, but it is below the highest speed lines set in China for 236 mph and way below airliner cruising speeds in the upper 500’s). What struck me was that this track set to extremely tight tolerances was tested with very heavy 39 ton axle loads that are the very top end of freight railroad axle loads for 3 years with with the equivalent of 13,000 100 car trains and “showed little deterioration in track geometry, directly translating into zero track maintenance due to surface, alignment, or gauge degradation.” While this type of tack construction is very expensive, it appears to have life cycle costing that is very competitive and potentially overwhelmingly. In the same section a German company’s track fixation hardware is noted that can facilitate micro adjustments for wear over longer periods. While US freight railroads are reluctant to share rights of way in close proximity to trains operating over the 100 to 120 mph limit. this data suggests this stance should be re-examined to allow more sharing of capital cost. Full high speed 200 mph operations may be better able to co-exist than generally thought. With liability agreements, positive train con
I agree, but I suspect there are monumental objections that will be raised to “why that can’t/won’t work here.”
[quote user=“RJSillars”]
The October issue of Trains magazine had two very diverse topics that got me to thinking. The issue was devoted to narrow gauge railroads railroads which had an enormous burst of development beginning almost 149 years ago. That burst was based on false hopes that by underinvesting in infrastructure great results could be obtained cheaply. That bubble created lots of fascinating, if ineffective, railroading. On the other hand the brief technology section at the beginning section of the magazine described revealing test of investment in track structure that was eye opening. Two test segments of slab track (continuous concrete bedded track) were laid at the FRA (Federal Railroad Administration) Transportation Technology Center Inc. near Pueblo. Colorado and set for very high speed tolerances (FRA class 9 for 200 mph operation) (No US trains run this fast or anywhere close, but it is below the highest speed lines set in China for 236 mph and way below airliner cruising speeds in the upper 500’s). What struck me was that this track set to extremely tight tolerances was tested with very heavy 39 ton axle loads that are the very top end of freight railroad axle loads for 3 years with with the equivalent of 13,000 100 car trains and “showed little deterioration in track geometry, directly translating into zero track maintenance due to surface, alignment, or gauge degradation.” While this type of tack construction is very expensive, it appears to have life cycle costing that is very competitive and potentially overwhelmingly. In the same section a German company’s track fixation hardware is noted that can facilitate micro adjustments for wear over longer periods. While US freight railroads are reluctant to share rights of way in close proximity to trains operating over the 100 to 120 mph limit. this data suggests this stance should be re-examined to allow more sharing of capital cost. Full high speed 200 mph operations may be better able to co-exist than generally thought. With l
You are right about the liability issue, but the intractable issues with CSX and MA and FL seem to have reached agreement when it looked hopeless. I think and hope there is enough mutual self interest to come to an agreement. It is probably the most serious problem.
I would agree that there are potential advantages in a combined rail corridor with mixed traffic.
- If nothing else, savings from consolidated grade separations of public and private crossings.
- Economies of scale for electrification substations and high tension feeders.
- Flexibility in traffic routing and optimized track utilization on multiple-track lines may require fewer costly tracks and overhead catenary.
The top of a contact rail is about as susceptible to icing as a wire. The former Chicago, Aurora & Elgin used ice scrapers to clean the 600-v third rail. Some railroads tried an under-running third rail to minimize the problem; others tried covers over an over-running third rail. Light weight third rail covers seem susceptible to damage which in turn can destroy pickup mechanisms and possibly cause a derailment.
The problem I see with a third rail is the limited safe voltage and need for many and more frequent costly substations to maintain sufficient traction voltage just from the material resistance, let alone resulting from the high current drawn for either high speed or heavy haul service. Furthermore, a very large contact area will be needed to avoid excessive temperatures burning up the contact mechanism. I think we just need to accept the clearance requirements for 25,000-volt overhead catenary; and perhaps 1,500-volt and limited current for slower speeds in urban areas with restrictive clearances.
Although as a childhood fan of the Roarin’ Elgin, the thought of the return of summer night showers of sparks as a bike was thrown onto the 3rd rail is nostalgic, it is also quite disturbing. Clearly electrified HSR and mid-speed rail in other countries is not using a 3rd rail for good reasons.