Heave Foundation Design
Heave Foundation Design
(OP)
I am designing foundation for a truck scale with a 3 footings of each about 120 kips. The manufacturer recommends footings of 4 ft x 13 ft. The allowable soil capacity is about 850 psf (silty sand and sandy silt). How can I avoid piling.





RE: Heave Foundation Design
Alternates to driven piles are AugerCast piles, Geopiers, cast in place concrete piers, etc. Whoever gave you the 850 psf capacity should be able to suggest means of improving the capacity.
RE: Heave Foundation Design
Dik
RE: Heave Foundation Design
RE: Heave Foundation Design
RE: Heave Foundation Design
The 850 kPa was proposed by a colleague professional who was also invloved in these often soft soil strata. I will be having a test pit to see the soil quality in the upper 10' using Torvane, Pocket PT and my thumb
RE: Heave Foundation Design
Kieran
RE: Heave Foundation Design
Also, are you concerned about Heave (in your title) or is that a typo and it's supposed to be Heavy?
RE: Heave Foundation Design
Onengineeer - try again please!!
RE: Heave Foundation Design
The title is Heavy Foundation Design (heave was a typo)
The locally presumed bearing capacity is 850 psf (the reported 850 kPa was incorrect).
My own field testing results had shown that the bearing capacity in the soft materials was 38 kPa (equal to approx 760 psf).
Sorry for the confusions.
RE: Heave Foundation Design
That is just above quicksand.....
Your are going to need some deep footings or pilings or something along those lines!!
RE: Heave Foundation Design
RE: Heave Foundation Design
The old mechanical truck scales used to be built on a pit - an open-topped RC box about 6 to 8 feet deep. Assuming your scale is about 65 feet by 9 feet and soil weighs 125 pcf, the excavated soil weighs 440 kips,more than your foundations,so you can have a balanced mat foundation. The walls provide beam strength, and the floor is designed as a mat spanning from wall to wall.
Be careful; it can float if the water table is high. An underdrain and sump pump may be necessary.
And the SM or ML is probably frost-susceptible. Frost can heave the pit and/or squeeze the sides in until the scale doesn't work. In cold country, I would put at least 2 inches of styrofoam under the floor and behind the walls.
RE: Heave Foundation Design