Snowmobile & Equestrian Bridges
Snowmobile & Equestrian Bridges
(OP)
I am involved in a project involving the conversion of a closed vehicular truss bridge into a bridge to be used by pedestrians, snowmobiles, and horses. Is anyone aware of design guidelines regarding a load combination for snow and snowmobiles/groomers, or bridge rail geometric and applied design load requirements for equestrian and snowmobile traffic? Thank you.






RE: Snowmobile & Equestrian Bridges
Hope this helps
RE: Snowmobile & Equestrian Bridges
There's a lot of details and design effort required for a item that's worth about $100K and these guys are much more efficient at providing them than we are.
RE: Snowmobile & Equestrian Bridges
My snowmobile weighs tips in at around 800lb, and if you add a 200lb man along with some snow in the track it is not a stretch that the total mass is around 1,200lb. A horse for riding will weigh in at around 1,200lb plus the rider and if you have a work horse, that number can increase to 2,000lb fairly easily.
If this bridge was in good shape and was designed for something like a HS20 or so, I doubt you will find a great deal of structural problems. The bigger concern in my mind is the safety requirments such as the railings. If this bridge did not have any pedestrian sidewalks you will need to consider this aspect carefully.
Brad
RE: Snowmobile & Equestrian Bridges
The bridges on that trail are Continental, I think, and seems like the nameplates show a 5,000 lb capacity.
RE: Snowmobile & Equestrian Bridges
Seems like you could easily get 4x crossing the same bridge at the same time: 2 pair, two abreast would fit walking. They'd not be running, so vibration would be less, but still ....
RE: Snowmobile & Equestrian Bridges
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Snowmobile & Equestrian Bridges
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Around 7600lbs with 2000lb payload. Roller and Drag add weight too.
Also note that medium sized excavators are often used for maintenance in the summer (ditching / swaling). The local club uses a JD120. That machine is over 12 Tons...
RE: Snowmobile & Equestrian Bridges
3.3—EQUESTRIAN LOAD (LL)
Decks intended to carry equestrian loading shall be
designed for a patch load of 1.00 kip over a square area
measuring 4.0 in. on a side.
C3.3
The equestrian load is a live load and intended to
ensure adequate punching shear capacity of pedestrian
bridge decks where horses are expected. The loading
was derived from hoof pressure measurements reported
in Roland et. al. (2005). The worst loading occurs
during a canter where the loading on one hoof
approaches 100 percent of the total weight of the horse.
The total factored load of 1.75 kips is approximately
the maximum credible weight of a draft horse. This
loading is expected to control only deck design.
If your bridge has a clear deck width greater than 10', it recommends using H10 loading without impact & without any other live loads. For a 7-10' wide deck, use H5.
RE: Snowmobile & Equestrian Bridges
1. A uniform loading of 85 psf for bridges 0 to 40' span and
60 psf for bridges over 40' applied to entire deck.
2. A uniform loading of 30 psf applied to entire deck plus a
concentrated load of 10,000 lbs at mid-span over an area of
8' wide x 10' long.
3. A horizontal wind loading of 30 psf on the net projected
vertical surface.
4. Deflection limits of L/200 for wood bridges and L/500 for
steel bridges.
You can find their "Bridge Guidelines for New and Replacement Snowmobile and All-Terrain Vehicle Bridges" at http://dn