slope stability vs bearing capacity on a slope
slope stability vs bearing capacity on a slope
(OP)
this is a pretty basic question as i am trying to understand the fundamental differences between slope stability and ultimate bearing capacity. I do understand the whole 2pi vs 1pi thing for bearing capacity vs slope stability.
if i have a shallow foundation at the top of a slope (assume homogenous soils), what is the difference between the ultimate bearing capacity, using say Myerhoff's equation (modified to account for the slope), vs the capacity given by a slope stability analysis?
Maybe i am picturing this too simplicitcally, but I imagine the failure plane for slope stability should look pretty close to the failure surface that the ult. bearing capacity formulas are based on.
I ask because I am getting some signficantly different results when I calc the bearing capacity by hand compared to when I do a slope stability analysis in slopeW. I would have expected them to be reasonably close to each other.
thanks for the help
if i have a shallow foundation at the top of a slope (assume homogenous soils), what is the difference between the ultimate bearing capacity, using say Myerhoff's equation (modified to account for the slope), vs the capacity given by a slope stability analysis?
Maybe i am picturing this too simplicitcally, but I imagine the failure plane for slope stability should look pretty close to the failure surface that the ult. bearing capacity formulas are based on.
I ask because I am getting some signficantly different results when I calc the bearing capacity by hand compared to when I do a slope stability analysis in slopeW. I would have expected them to be reasonably close to each other.
thanks for the help





RE: slope stability vs bearing capacity on a slope
If you aren't getting results that close, could be a calculation error or a modeling error.
If you post more info, someone may be able to help out more.
Good luck.
Mike Lambert
RE: slope stability vs bearing capacity on a slope
Bearing capacity is basically bound by the ultimate shear strength of the soil. So is slope stability. It seems to me the question of bearing capacity for the reinforced zone acting on teh native soil is properly addressed by the global stability evaluation(s).
Maybe I'm just agreeing with you or feel your confusion. . .
f-d
¡papá gordo ain’t no madre flaca!
RE: slope stability vs bearing capacity on a slope
From a gross movement prespective I agree that there is no reason to check bearing capacity for a segmental block wall. However, from a long term settlement prespecitve (at least with clay foundation soils), checking bearing capacity gives a somewhat implict settlement check. Also, with some wall systems the load under the facing material can be a fair amount higher than the average bearing pressure in the reinforced zone and settlement of the face can look really bad.
Mike Lambert
RE: slope stability vs bearing capacity on a slope
If one of such solutions is used, I would expect a closer result to the slope/W analysis, but I would be really surprised if the results were very similar, since the algorithms and the theory behind them are significantly different.
There might be a closer affinity if an undrained analysis is carried out, since the surface could be a circle in both cases, according to the failure surface shape chosen.
Bottom line: I would use the slope/W result since the geometry of the problem is specific to your case hence more exact.