Search results for query: *

There is nothing unusual about slip circles exiting at the toe, and it’s important to know how different assumptions can affect the resulting FoS. I thought we’d agreed that mathematical sophistication is often unnecessary along with the need for a supercomputer. Nor do I have a preferred...

Responding to the comment that the Spencer and half-sine methods would change the FoS by about 1 part in a 1000, it would seem to make no sense for Slope/W to allow for different guesses at the shear force function if these made no significant difference. I expect such differences can arise...

Thanks BigH for pointing out the usefulness of slope stability charts. So the consensus in this thread isn’t in favour of mathematical sophistication - the main sources of error lie within the physics. GeoPaveTraffic mentioned side forces being zero at the ends of the slip surface. The...

I think you make some good points GeoPaveTraffic. I’d rather use a simpler method that I know makes sense and can be directly checked than something that takes longer and can’t realistically be checked personally. One could use two completely different FE programs but that’s more time and...

Thanks geotechguy1 for your comprehensive reply. I expect Krahn and Fredlund have done well financially from their allegedly general method of limit equilibrium, but even in the developed word not all engineers can afford software like Slope/W and not all problems warrant investing much time...

You could also have mentioned the problems of soil variability, sample disturbance, testing relevance, matric suction, tension cracks, climate change and vegetation unknowns. We seem to be in agreement about the risk of trying to be too clever about analysing stresses. Bishop’s method has the...

Thanks GeoPaveTraffic. Yes I've seen Spencer's method, and having looked more closely at Krahn’s splendidly clear paper it seems obvious that the General Limit Equilibrium Method should really be called the Generalised Spencer Method. It takes advantage of Spencer’s innovation of two factor of...

Maybe I'm talking about square pegs and holes with rounded corners. But I still think there's a need for the relative simplicity of the method of slices which doesn't either ignore internal shear or else involve a choice of seemingly arbitrary functions tied to horizontal forces. Why not...

OK but these don't seem to provide a relatively simple method of slices that tries to directly take account of typical deformations.

Thanks for your reply, and I agree that making things more complicated isn't always better, but the method you refer to seems to involve an FE analysis of the specific slope. What I meant was a replacement of the X=E.λ.f(x) approach by a generic function obtained from different FE analyses...

In the Morgenstern-Price method the ratio between the inter-slice (vertical) shear force and the inter-slice normal (horizontal) force is often defined by a half-sine function. So the ratio would be zero at both ends of a slip surface. Yet the normal force near the top of the slip surface...