1st time poster. Late this past evening, was sitting in my recliner, journaling. Heard train horn as usual in distance. Then “felt” prolonged rumbling from what seemed to be a fairly long train running on tracks. I live on a hillside above the river valley where the trains run.
Two questions came to mind.
What is the maximum amount of freight train cars permitted for one train in the state of PA?
When I hear/feel the rumbling when a freight train w/ many, many cars travels on the tracks, is that just an auditory thing and /or is energy transmitted via the rails through the ground, similar to an earthquake?
Thanks in advance. Could not find the answers by doing several searches.
There is no train length limit. No state has any authority to impose such a limit. Rail operations are considered interstate commerce and regulated by the Federal Government. They have no limit on train length.
Greyhounds is right. I studied the Supreme Court decision resolving that issue in a Constitutional Law class many years ago. If my memory serves me right, the decision came in 1915 and struck down an Arizona law which limited train lengths to 70 cars.
There are so many dynamics and laws of physics to your questions. Trains are restricted to number of cars by weight, car type, load type, route, engine power, track, weather, and other conditions. Rumbling sounds from above a valley can be different at different times not only because each train is different in some way but also because grade up or down, weather conditions like temperaturet, humidity, fog, rain, snow, or clear and dry, etc. all have an effect. Also, heavier commodities, like coal, will make more vibrations than other lighter commodities. Going over a rail joint, a flat spot on a wheel, dragging or stuck brake, dynamic brakes, throttle positoin on locomotive, are also some ot the physical aspects of vibrations and rumblings. I live a little less than a mile and across the Susquehanna River from the NS Southern Tier line and can “hear” trains and “feel” trains coming and going for maybe two or three miles in each direction. Sometimes it seems like an earthquake while at othertimes you barely hear a faint rumble while still other times you don’t hear a thing until there might be a horn blast for a distant road crossing. So, no firm answer. But you have the joy…and for some, the comfort…of figuring out what you are listening to and learning the fun of train watchhing, listening, and feeling!
“It depends” - mainly on local geology and soils, plus topography (shape of the land), direction of train and wind, etc., which could influence the direction and energy of the sound waves.
How close are the tracks to you at the closest point ? Do the tracks run through any rock cuts or excavations nearby ? Those link the tracks pretty closely to the underlying rock, and also concentrate the sound into a kind of echo chamber. Is there a stream between you and the tracks ? Those can sometimes act as vibration isolation, esp. if there’s a fault or rock joint underneath them - that’s likely why the stream is there in the first place. In contrast, if the tracks are on soft or marshy ground, then what you’re feeling is likely just sound waves coming overland, because the ‘muck’ will absorb the energy imparted to the ground.
Keep in mind that sound waves come in many frequencies, and those from trains that might be below hearing ability - somewhere between 20 and 60 Hz. (= roughly 50 to 15 ft. wavelengths, respectively) depending on your age, other noises, etc. - can still vibrate structures which have dimensions close to those wavelengths, such as house walls, cars., etc. (Think of ‘sub-woofers’ and the kids with the loud stereos in their cars, which can vibrate your car or house even though you might not be hearing much more than a ‘thump-thump’ sound in the distance.) Alternatively, in Pennsylvania there are a lot of folded rock layers in the geological structure of the hills and valleys - the same phenomenon that causes “artesian springs”, for example - so if the train is
I’m going to go with the idea that you can feel it as well. at my old office, I was about 4 blocks from the base of a hill on a BNSF line. I could usually tell when a train was going through, even when I couldn’t hear it.
My thoughts to Carkeys: As Paul North said; WELCOME here! [#welcome]
You don’t indicate where you live so it is kind of hard to get a picture of your particular situation. I lve about a quarter mile east of a double tracked section of the BNSF Southern Transcon. Soil around here is pretty much alluvial types, and we are in the flood plain between two rivers. Viberation would not be as conductive here as if there were a shallow hard rock base under us.
Recently, my wife commented that she was feeling certain trains that were causing here to feel vibrations as she worked on her computer in early AM. The traffic tends to be fast Double stackers and loaded grain trains. I made the statement at the time that the track might have developed some 'rough spots;, sure enough, a couple of days later late at night, I watched one of the LORAM Grinders making slow passes on the BNSF. She has not complained since of ‘shaking’ in the mornings due to passing trains.
As a kid, I would go shopping with my mother in downtown Baltimore. Occasionally, we would have lunch or a snack at the Hutzler’s Coffee Shop that was located in the basement of their 5 or 6 story department store that was located on Howard Street…directly above the B&O’s Howard Street tunnel…you knew every time the B&O had a movement through the tunnel…up grade or down grade, full train or light engines. You could see the liquids vibrate in their containers on the table in front of you.
I lived on the hill above B&LE’s yard near Universal, PA (Penn Hills) for several years and I can say with authority that you CAN feel a heavy train moving. Trains ducked into a tunnel at the south end of that yard and transfer jobs could sometimes be heard until the head-end entered the tunnel. The wind speed and direction, air temperature and humidity had a lot to do with whether or not you heard those trains (you could very seldom hear trains entering the yard from the other direction nor could switching movements be heard). But you could feel the vibrations of iron ore loaded hoppers long after the sound of the power was cut off by the tunnel.