I am looking for the best slope stability software, for the best price, that also calculates fos for reinforced slopes as well as for seismic loading conditions.
The program you need to purchase may depend on the requirements of your clients. For example, if you do much state DOT work, the DOT may have a particular program they want you to use.
I've finally got to the stage where I am using the Finite Element Method for the majority of slope stability analysis, and especially for any slopes that incorporate structural elements such as walls, tiebacks. The method was summarized by Giffiths & Lane in Geotechnique way back in 1999 where they concluded:
"It is argued that the the finite element method of slope stability is a more powerful alternative to traditional limit equilibrium methids and its widespread use should now be standard in geotechnical practice".
is a widely used program that will provide you with the information for approximatelt $1,200 (US) and has good graphics, used friendly windows environemnt and we can usually have our engineers learn program immediately.
which is on the order of 3,500 or so. Complicated but great technical program with great Autocadd integration, and great graphics. Will also do probabilty analysis, etc.
SLIDE is a great program that has a good interface for performing limit equilibrium analyses. The files from SLIDE can also be used in PHASE2 where finite element slope stability can be completed. Finite element slope stability is good but has not replaced limit equilibrium by a long shot. Also PHASE2 can be used to compute insitu stresses from things like embankments and then the user can define a soil strength equation so the shear strenght of the soil can be calcluated at a number of points, i.e. a grid, and the grid can be imported into SLIDE. This is a very good and advanced way of performing undrained analyses for clay.
by Adama Engineering, recognized as one of the leading segmented retaining wall desogn programs. Fairly flexible, about $1,000. The company is difficult to deal with, but it is a good program (see web site).
After reading this thread folk might get the idea that limit equilibrium and finite element analysis are the only options for slope stability analysis. But you could use finite differences, e.g. the FLAC/SLOPE program, see:
Or how about discontinuity layout optimization, which seems to be simple like limit equilibrium but general like finite elements. LimitState:GEO is based on this, see:
In my experience Slide has the best bang for the buck. Slope/W may be comparable in features, but cannot beat Slide in price. I also think Slide is slightly easier to learn. UTexas may be powerful, but does not have a graphical interface. And other graphical software which can interface with UTexas haven't helped that much in making things easier.
I think that FEM is most likely a waste of time. Most engineers and geologists seem to have a hard time coming up with a realistic subsurface model of a site as it is. Any engineer that has spent a lot of time looking at open excavations knows how variable a site can be, at least here in California anyway.
As a wise old geotechnical engineer once reminded me....engineers evaluate slopes, not computer programs.
I suspect that cdstan has bought the software by now.
However, I have used SLIDE and SLOPE/W and both seem to have similar features but sometimes dealt with in different ways, e.g. anisotropic strength functions, and one method may be preferable to the other depending on your requirments. SLIDE is however considerably cheaper and I found it much easier to use, particularly the CAD import / interface but then I was already familiar with PHASE2. Technical support from Rocscience (SLIDE) is excellent but I have not tried it with SLOPE/W. Both cater for reinforvcement and seismic loading.
I used GEOSTRU some time ago and it was good for the price. Although such cheaper programmes are adequate for simple analyses, check if they have the facility for Hoek-Brown parameters, probabilty, sensitivity, strength functions etc. if these are likely to be required.
With regard to "Garbage in-Garbage out", yes, elastic parameters are not easy to define but if you are using plastic analysis and Mohr Coulomb parameters with FE, these are the same garbage that you would input into limit equilibrium. As usual, it is horses for courses, sometimes limit equilibrium analysis gives more flexibility to analyse a particular problem.
I don't know much about SVSlope but have used LimitState::GEO quite a lot recently. Like finite element packages it can be used for pretty much any geometry of geotechnical problem - not just slope problems. But unlike finite elements there are very few input parameters to worry about and it is very quick and easy to use (and the output is clear too). The solutions generated are rigorous plasticity ones, rather than limit equilibrium.
For slopes the biggest thing to get your head around is that it reports a factor of safety on an applied load (can be self weight and/or surcharge), rather than a traditional global factor of safety (i.e. resistance/disturbing action). This is initially disconcerting but fine if you are designing to the new Eurocode 7 (using design approach 1), which applies partial factors on material strengths, and you just need to check that the factor on the load is >1.
Finally - LimitState:GEO does do nails, but apparently no seismic capability yet...