blue streak 1 Question. Did N/S claim that their very great computer program proved that the cars would meet the crush strength requirement. Didn't it petition for a FRA waiver not to have to actually do the test just take their wonderful computer calculations instead ? Yes I just love computer work. Garbage in garbage out.
Question. Did N/S claim that their very great computer program proved that the cars would meet the crush strength requirement. Didn't it petition for a FRA waiver not to have to actually do the test just take their wonderful computer calculations instead ? Yes I just love computer work. Garbage in garbage out.
I'm not aware of any waivers to use computer simulations to replace a squeeze test, but doesn't mean it didn't happen. There is actually little incentive to do so as the test is relatively easy and cheap to conduct and if successful the sample car shell can be fitted out as a production vehicle.
Where there has been some incentive to use simulation models in place of physical testing is in the VTI limits for cars operating at the high end of the speed spectrum. The physical tests require the use of an instrumented wheelset and several days of testing which can be quite expensive. The vehicle dynamics models available are quite good, NUCARS in the U.S. and Vampire in the UK as well as several models propritary to the builders. The has been some effort to allow the use of model results for these requirements. And As always the danger is to ensure that the suspension elements are correctly characterized in the model.
Dutchrailnut the problem is that car as designed, does not meet the 1000 000 lbs crush load strenght as per FRA rules, it buckled at 800 000 lbs a standard used over 10 years ago. so untill car is redesigned the workforce is laid off.
the problem is that car as designed, does not meet the 1000 000 lbs crush load strenght as per FRA rules, it buckled at 800 000 lbs a standard used over 10 years ago. so untill car is redesigned the workforce is laid off.
The question is, is the fundamental design at fault, were there modifications made to that design at the factory for whatever reason, or were there defects in the manufacture of the car (ala the missing welds on the first batch of CTA 5000 series cars)? And the word is the car never got to the 800,000 lb level before failing.
There are other issues with the 800,000 limit in the first place but that's another story.
[from FRA]
The Federal Railroad Administration (FRA) is developing new regulations addressing the occupant volume integrity (compressive end strength) of passenger rail cars. The new rules are being adopted to accommodate the introduction of rail equipment designed to alternate standards that will provide a level of safety equivalent to that of conventionally-designed vehicles. The fundamental change in the regulations involves applying the proof load on the collision load path rather than on the line of draft, as has been longstanding U.S. practice. Alternativelydesigned passenger equipment must be shown to comply with one of the following loading scenarios:
• 3,560 kN (800,000 lbf) with no permanent deformation
• 4,450 kN (1,000,000 lbf) with limited plastic deformation
• 5,340 kN (1,200,000 lbf) without exceeding the crippling strength of the car.
[Previous] FRA regulations require that Tier I passenger equipment (with maximum operating speed of 200 km/h [125 mph]) sustain a static compressive end-load of 3,560 kN (800,000 lbf) applied longitudinally on the line of draft without permanent deformation. This traditional approach to demonstrating OVI is relatively simple to accomplish. Since it is intended to be non-destructive to the test article, the required load is applied and released, and measurements and visual observations confirm or refute the absence of permanent deformation. Passenger rail equipment built to alternative design standards generally incorporates crash energy management (CEM) principles and employs crush zones and deformable structures outboard of the occupant volume which collapse during impact and absorb collision energy while preserving passenger survival space. In order to provide maximum effectiveness, CEM-equipped vehicles must possess a strong occupant volume to ensure that vehicle crushing is restricted to areas outboard of the occupant compartment. As such, this equipment will generally not pass the traditional line of draft buff strength test since permanent deformation cannot be avoided.
C&NW, CA&E, MILW, CGW and IC fan
Electroliner 1935Reminds me of the old classic New Yorker cartoon of a biplane heading into the ground and the pilot parachuting down, with the emergency responders rushing toward the crash scene and Executives looking on in horror, while an smiling design engineer with his slide rule on his belt and carrying a roll of blueprints walks away from the field toward you saying, "Back to the drawing board". For the younger audience, slide rules were used before calculators became common in the early 60's.
Reminds me of the old classic New Yorker cartoon of a biplane heading into the ground and the pilot parachuting down, with the emergency responders rushing toward the crash scene and Executives looking on in horror, while an smiling design engineer with his slide rule on his belt and carrying a roll of blueprints walks away from the field toward you saying, "Back to the drawing board". For the younger audience, slide rules were used before calculators became common in the early 60's.
Buslist Heard from (as Roger Ford calls it in Modern Railways) Informed Sources, that the initial squeeze test of the prototype bi level car did not go well. There was significant deformatiom well below the 800,000# level. So there will be further delays on the delivery of these cars. But if the Govener of Illinois has his way the Illinois cars will be surplus anyway.
Heard from (as Roger Ford calls it in Modern Railways) Informed Sources, that the initial squeeze test of the prototype bi level car did not go well. There was significant deformatiom well below the 800,000# level. So there will be further delays on the delivery of these cars. But if the Govener of Illinois has his way the Illinois cars will be surplus anyway.
I see the failure hit the Trains news wire today. They say that they are not sure what the problem is.
Superliner in service 1979. Superliner II in service 1994. California Car in service 1996. Surfliner in service 2000. This really isn't all that hard, folks.
Editor Emeritus, This Week at Amtrak
Il Duce is finding out that being Governor of Illinois is quite different from being the CEO of your own hedge fund. The General Assembly is starting to push back on several issues.
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