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Load from freight train 1

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Da Vinci

Structural
Joined
Dec 20, 2017
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5
Location
UA
Hi guys,

I am excited with such question, how can the freight train affect a foundation (piles), how it can be considered and what load to put on a retaining wall, someone faced such tasks? Can anyone direct me to any ideas?

Thanks
 
 http://files.engineering.com/getfile.aspx?folder=5f1659e5-3041-4ccd-a231-6456a560b4e2&file=Plan_and_section_FND.pdf
the AREMA manual will give you the loading (Cooper E80, which you can also just google) and other pertinent information related to the design of structures exposed to train loadings.

As for the effect on piles, depends on soil types so best consult the geotechnical engineer on the project.
 
Generally, for the lateral surcharge pressure acting on a wall or foundation piles, you take the maximum specified train's axle load and then divide the axle load by the axle spacing and the track's tie width. Then, you use a Boussinesq strip load surcharge with the vertical pressure acting on a strip width equal to the tie width. For example, AREMA's Cooper E80 train surcharge is an 80,000 pound axle divided by a 5' axle spacing and an 8.5' tie width = 1882 psf vertical surcharge on an 8.5' width strip. You should check with the particular railroad with which you are working for their surcharge requirement. Some railroads also require you to multiply the vertical surcharge by an impact factor. For vertical loads acting on foundation piles, you will have to design the substructure foundation to get the vertical loads on the piles.

 
I once had a job where a corrugated metal culvert had been under a rail road as a pedestrian passageway under an embankment carrying the railroad (one track). In the construction handling of it the elliptical shape was severely bent such that some feared that it might collapse under the train loading. Top of passageway was about 2 to 3 feet under the ties. Seeing the distortion (after the job was a year or more old) locals decided to close off the use due to possibly a failure. Trains were carrying iron ore. I set up dial gauges on adjustable "pipe" supports to measure both vertical and horizontal deflection. The plan was to see if continuing distortion would eventually result in failure. I was able to have control of the position of standing units of the train, as well as observing the conditions with moving train. Over a period of a month or so periodic measurements were made. The measurements were stopped when it became clear that no permanent distortion was present from start to last observation date. Deflection in both vertical and horizontal directions was readily observed with the set-up as the loads came and went. They were well within the range of the 2" throw dial gauge range. Interesting to note the locomotive caused deflections were significantly less than the loaded cars. The deflections were clearly in the elastic range in spite of the severe distortion of the "tube"..
 
Thank you all for your advice!
 
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