Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
(OP)
I have a concrete wall footing that I am designing for a rodeo. I have attached a picture of the wall footing.I have a question regarding impact loads. Since this wall is being built to separate the grandstands form the rodeo arena where the animals will be,Do any if the codes mention designing for an impact load caused by animals in an arena? Should I apply a distributed load along the face of the wall on the other side of the bleachers/grandstands? If I should apply a load, what would be acceptable (maybe 200 psf, 150 psf, or 100 psf). Any suggestions and/or comments are appreciated.






RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
On your drain detail, the gravel serves no purpose. Instead just use a perforated pipe with a geotech "sock" covering to keep the sand out of the pipe.
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
Second, calculate the stiffness of the wall. k = the inverse of the deflection (inches) due to a 1 kip load applied at the top of the wall. In other words, k = 1/Δ.
Third, calculate the deflection (inches) caused by the kinetic energy calculated above. Δ = the square root of [(KE)(12)/k].
Finally, you can determine the force of impact (kips) caused by the animal by multiplying the deflection calculated in step three by k determined in step 2. In other words, F = (Δ)(k).
DaveAtkins
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
@ DaveAtkins - I do not know the weight of the animal nor the speed they move at. Do any of the codes provide this information?
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
@ everyone/anyone -Since I am having issues with sliding check for my wall, if I dowel in the pavement shown in the picture to my wall footing should that eliminate sliding of the wall? We are building a new pavement and wall, so I can have the 2 attached together. Does anyone foresee any problems/issues?
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
Also, another thing I would add is this point load would be spread across a length of a footing, not a one foot section. So your resisting moment should be weight of concrete per area times the length of your footing.
So you could say
Resisting Moment = Weight of footing*entire length
So if your footing is 20 feet long, you could say, 6 ft tall * 1 foot wide * 20 FT LONG * 150 lbs/ft cu = 18000 lbs
and also! the weight of your foot 5*1.5*20*150=22500
Then for the Resisting moment = (18k+22.5k) lbs*centroidx, which would be half your footing length so
40.5k*2.5 ft =101,250 ft lbs
Overturning Moment = mass of cow*approximate speed of cow*height of footing
Weight of cow =4600 lbs
mass of cow = 4600lbs/32.2 lbs/s^2=143 lbs m
momentum of cow (lets say 15 mph to 22 ft per second) = 143 lbs m * 22 ft/s = 3146 lbs F
Give it, a safety factor for time purposes say 5,
3146*5=15730 lbs F
multiply by entire height of wall so, 15730*6 = 94380 ft lbs
So resisting = 101250 ft-lbs
and overturning = 94380 ft-lbs
which resisting>overturning with a safety factor of 5.
I think impact loads should be a concentrated load.
Unless you have a stampede of cows... then you have a serious issue. =)
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
@ SteelPE - 6000 lb is quite a force. The drawing I have attached is what is existing at the site right now. We also took pictures (please see additional attachment). The timber planks you see are currently cover up the existing concrete wall that we will be replacing.
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
RE: Soil bearing, Overturning & Sliding check for Concrete Arena Wall Footing
you are going to take a 1 foot wide footing, and have a bull ram into it. No offense but I just don't see the logic. Then you would have to take your cow point load and distribute that along the entire wall.