Construction PE
Well-known member
Does anyone out there have a chart/list of allowable soil pressures by Type?
I am working on Problem 79.9 (Practice Problems book by Lindeburg- 11th edition). I am Construction and has hoping to reach out to all you Geotechs out there.
79.9- A 50 ton crane with 4 extendable outriggers weighs 90,000lbf. The crane is set-up on Type A soil. Approximately what area of cribbing is needed under each outrigger?
The problem is pretty simple...
The max load that would ever be placed on one outrigger (before tipping) = weight crane + weight of load
Max load = 90,000lbf + (50 tons x 2,000 lb/ton) = 190,000lbf max
The solution states the allowable soil pressure for Type A soil is 1.5tsf (with no reference).
Stress allowable = load / area
(1.5 tsf X 2000 lf/ton) = 190,000 lbf / Area
Area = 63.3 sqft
My problem is I could not find the 1.5tsf listed. I would hate to miss a problem like this.
Does anyone have a link to a list of allowable soil pressures for each type of soil?
Thanks!
I am working on Problem 79.9 (Practice Problems book by Lindeburg- 11th edition). I am Construction and has hoping to reach out to all you Geotechs out there.
79.9- A 50 ton crane with 4 extendable outriggers weighs 90,000lbf. The crane is set-up on Type A soil. Approximately what area of cribbing is needed under each outrigger?
The problem is pretty simple...
The max load that would ever be placed on one outrigger (before tipping) = weight crane + weight of load
Max load = 90,000lbf + (50 tons x 2,000 lb/ton) = 190,000lbf max
The solution states the allowable soil pressure for Type A soil is 1.5tsf (with no reference).
Stress allowable = load / area
(1.5 tsf X 2000 lf/ton) = 190,000 lbf / Area
Area = 63.3 sqft
My problem is I could not find the 1.5tsf listed. I would hate to miss a problem like this.
Does anyone have a link to a list of allowable soil pressures for each type of soil?
Thanks!
