Amtrak Derailment @ Kensington - Trains Magazine
Railroads attempt to lay rail at a given temperature that will allow the rail to normally handle stresses (expansion/contraction) over a normally expected temperature range for a given region. This allows the tremendous pressures to be handled by the roadbed, track, ties or clips, spikes, tie plates, ballast, etc. in a balanced/manageable way. Too hot, the rail kinks (buckles); too cold, that same rail pulls apart (breaks). The target temperature is the temperature of the rail, NOT the ambient air temperature. The rail is usually much warmer than the outside air temperature. On the old Santa Fe, your "target temperature" for laying rail was 95-120 degrees, dependent on location. You often saw track gangs heating up 1440 Ft. strings of rail with massive propane heaters to get rail to the right temperature. If you don't get rail to the right temperature, your railroad's roadmaster and track forces are out there for months trying to "destress" that improperly laid rail (Time and money that costs a railroad dearly) and get the rail to behave normally. The FRA and the railroads have emphasized the importance of managing and destressing CWR for the last 10-15 years. I would imagine that the target temperature for the rail at Kensington was somewhere between 80 and 95 degrees (CSX has that info published internally somewhere). The rail temperature on the day of the derailment was probably well into the three digit range (and that area was suffering a record heat wave)....The rail may well have been laid at the proper temperature and other factors may have come into play - do NOT expect to see an immediate and definitive answer on the cause of the derailment. The sun kink was the result of some other risk factor in the mix, i.e. "what allowed the rail to kink and what was the trigger that set it off?.....Look for the FRA and the NTSB to be looking at other maintenance activities such as spot surfacing, defective rail replacement, lack of shoulder ballast, undercutting, recent tie replacement and so on.
It doesn't matter if the ties are concrete or wood, if the fastenings are spikes, pandrol clips or E-clips, etc, ...Given the right conditions, any track can buckle or somehow fail.
With the clueless boobs in the media reporting on this to an equally clueless general public, the answer may never be clearly reported. Politicians will clamor for some legislative fix-all for the FRA/NTSB to enforce while what is currently on the books is more than sufficient and a re-emphasizing of certain rules/ principals is all that is really needed. Too bad the accident happened, the timing is lousy for Amtrak and CSX.
Mudchicken Nothing is worth taking the risk of losing a life over. Come home tonight in the same condition that you left home this morning in. Safety begins with ME.... cinscocom-west
