Is any acceptable range of Lambda in slope/w?
In stability analyses, sometimes very weird slip surface come up for the critical slip surface, especially when we perform "block search". Then if we plot the FS vs Lambda, very possibly the converged Lambda value is less than say minus 0.2. Do we have any empirical range of Lambda, which is corresponding to the acceptable solution? Otherwise, the block search approach is basically useless。
BTW， what are " root finder" and "Linear Search". Try to understand them, nowhere we can find the explanations.
Thanks
Shan
Answers
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Hi Shan, the actual value of lambda doesn't matter, only good convergence between moment and force equilibrium matters. I would recommend reading sections 2 and 3 of the Slope Stability Modeling manual, which covers the theory of the limit equilibrium method and the different slip surface search techniques. Here's a video on our YouTube channel that also discusses these topics as well as Root Finder vs. Linear Search: SLOPE/W Convergence
You may also be getting a physically inadmissible slip surface even though SLOPE/W calculated a factor of safety, in which case you can ignore it and use the lowest factor of safety of the physically admissible slip surfaces.
Additionally, you can find descriptions of Root Finder and Linear Search in the Define Project topic in the Help menu.
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