Become one with your modeling tool

I’ve just made our examples (aka Resource CD) available on the geo-slope.com web site.

It works nearly the same as in GeoStudio 2007 itself, but has the distinct advantage that you don’t have to download the 515 MB CD image (you still can if you want to)! 

Just search online, scan the results for something of interest, and click “Open the gsz” to open it in GeoStudio.  From GeoStudio you can choose Save As if you want to save a copy locally.

Most examples also include a pdf that describes the thinking behind the model.  Some include a movie generated by GeoStudio showing the computed results.

The online examples will also be updated regularly.  We tend to add a few more every couple of months, so check back often.

Comments and Emails

On an unrelated note, thank you to those who have been emailing me with feedback and questions.  Writing a blog is so much more interesting when you hear back from your readers!

To those of you silent lurkers, know that you are very welcome to continue reading without commenting, but also that I do welcome your comments and questions on this blog or by email (I prefer comments on the blog because they allow everyone to benefit), and I always try to respond quickly.

Here’s a pretty hidden feature…  did you know you can have GeoStudio solve a whole bunch of analyses and even files automatically?

Solving an Analysis

GeoStudio can be run with command-line parameters that tell it to solve one or more analyses and then shut down.

For example:

geostudio “c:\my file.gsz” “an analysis” /solve

will solve the analysis named “an analysis” in the file “my file.gsz”.

Solving Several Analyses

A bit more interesting:

geostudio “c:\my file.gsz” /solve:all

will solve all analyses in “my file.gsz”.  It solves them in the right order, so that a steady-state analysis, for example, gets solved before the transient analysis that uses its results as initial conditions.

Logging

If there are errors during the solving process, however, you don’t normally want an error message to pop up, because then the whole thing stops and waits for you to hit OK, instead of moving on to the next analysis which may solve just fine.

Specifying a log file like this:

geostudio “c:\my file.gsz” /solve:all /log:”c:\log.txt”

will cause all errors to be written to “log.txt” instead of being displayed on the screen.  After it’s done solving everything you can open log.txt in Notepad and make sure everything ran properly.

Exiting

After GeoStudio is done solving the analyses you told it to, it just sits there with the file open.  If you want it to close when it’s done, use /autoexit:

geostudio “c:\my file.gsz” /solve:all /log:”c:\log.txt” /autoexit

Batch File

Put all those together and you can write a batch file to automatically solve several files in a row.  For example, use Notepad to create a new file named “solve.cmd” with this content:

geostudio “c:\my file.gsz” /solve:all /log:”c:\log.txt” /autoexit
geostudio “c:\my other file.gsz” /solve:all /log:”c:\log.txt” /autoexit

When you run it (double-click the file) GeoStudio will launch and solve all analyses in “my file.gsz” followed by all analyses in “my other file.gsz”, and log.txt will contain the combined logs of all analyses.

Real-Life Application

Is this a useful feature?  I’m not really sure.

It’s very useful for us, it’s a core part of our Quality Assurance process.  Every night we have two quad-core servers crunch away for half the night solving several hundred analyses and comparing the results to make sure we didn’t inadvertantly break something.

But is it useful to the average (or above-average) geotech engineer?  I can imagine a few situations it might be, but I don’t know if they’re realistic or just contrived.  If you have some VADOSE/W analyses that you know will take several hours to run, you could start them in batch mode before going home at the end of the day and have the results ready in the morning. 

Or if you have a large number of interdependant files, and you make a change to one analysis that all the others depend on, you could run a batch to re-solve all the others.

What do you think?  Could you see yourself using a batch file to solve a large number of analyses?  Do you already?  I’d love to hear about the processes you follow in your office to manage all the analyses you must encounter in a large project.

When creating a large number of analyses, sketch text can be difficult to deal with.  Until version 7.1, sketch text has been “global”–you add it once and it is displayed in every analysis.  That’s great for things like titles or some results, but no good if you want to display text that only makes sense for one analysis.

A couple of important changes have been introduced in 7.1 to make it easier to control where text is displayed.

Text in Define vs. Contour

We’ve long differentiated between text intended for Define and text intended for Contour.  That feature has not changed.

If you create text when you are in Define, the text is forever associated with the Define view.  It will always be displayed if you are in Define.  When you switch to Contour, there’s a view preference to choose if you want Define sketch text to be displayed or not.

Likewise if you create text when you are in Contour, then you switch to Define, a view preference lets you choose if you want to display the Contour sketch text.

Hide Text with Invalid Fields

New in 7.1, if a block of sketch text contains a “field”, and if you’re in a view where this field doesn’t make sense, the entire block will be hidden.

For example, say you’re in SLOPE/W Contour, and you add some text to display the factor of safety:

When you switch to Define, or if you switch to a SEEP/W analysis, there is no factor of safety, so the text will not be displayed.

Analysis-Specific Text

For even more control, you can choose to display text in only one analysis.  In the Sketch Text (or Modify Text) dialog, select “Current analysis only” in the “Show in” list, and this text will only appear in the analysis in which you create it.  Select “All analyses” and the text will always be displayed (subject to the “Hide Text with Invalid Fields” logic I just mentioned of course).

You can always change that option later using Modify Text.  If you want to start displaying sketch text everywhere instead of only one analysis, go to the analysis where it’s viewed, use Sketch - Modify Text, select the block of text, and change the “Show in” to “All analyses”.

Cloning Analyses with Analysis-Specific Text

If you add some text to an analysis with the “Current analysis only” option, then you go into KeyIn Analyses and you clone the analysis, the new analysis will have a copy (or clone) of the text.  Change the text in one analysis and it will not change in the other analysis.  You really have chosen to only display that text in one and only one analysis.

Text Suddenly Appears, Then Disappears

When you’re in Sketch Text or Modify Text mode, all sketch text for the current analysis will appear, even text with invalid fields.  (Otherwise there’d be no way to modify or delete text with an invalid field, as you could never select it.)

So if you find that in Sketch Text mode you have lots of text, but as soon as you exit the mode the text disappears, it’s likely because there’s an invalid field in the text.  Choose Sketch - Modify Text from the menu, and read the text that reappears.  If there’s an invalid field, it will tell you so:

FOS: Could not find field “CurrentResults.CurrentSlipSurface.SlipFOS”

Click the text to edit it, and delete or fix the invalid portion.

Summary

Version 7.1 tries to be somewhat smart about what sketch text to display by hiding any text that does not apply to the current analysis.  You can help it further by specifying that text is only for a specific analysis.  If you’re puzzled by disappearing text, it’s likely because of an invalid field, which you can fix using Modify Text.

Steve asked me a few weeks ago to write about multi-stage rapid drawdown, and how it has changed in version 7.1.  This is a bit outside my comfort zone as a non-engineer, but I’ve taken a rapid drawdown crash course from a couple of our in-house experts, and here’s what I’ve found.

Background

The concept is simple, but the feature has evolved over the last few point releases.  The solver simply needs to know the water level before the drawdown, and the water level after the drawdown.

Pre-Version 7

My understanding is that it is not possible to do staged rapid drawdown with SLOPE/W version 6 and earlier.  If there was some way to do it, it would have involved multiple analyses and manually changing material properties between runs.  I’m not familiar enough with the theory to know if that would even be possible though.

Version 7.00-7.02

Beginning with version 7.00, SLOPE/W adds direct support for staged rapid drawdown analyses, using the 3-stage undrained strength method proposed by Duncan, Wright and Wong (1990).

The feature was first implemented with a very simple conceptual model:  draw a single piez line identifying the “full” water level, and tell SLOPE/W how far down the level will drop (the “drawdown distance”).  The solver will compute the lower level by simply subtracting the drawdown distance from the x coordinates of the piez line.

There are only two steps you needed to take:

1. In KeyIn Analyses, select the “Staged Rapid Drawdown” option on the Settings tab, and enter a Drawdown Distance.

2. Use Draw Pore-Water Pressure to draw the “full” piezometric line.

Version 7.03

We were quickly told by clients that this approach was too simplistic.  It covered some simple cases, but often times the “empty” position was not a uniform drawdown of the “full”.

So in version 7.03 you no longer enter a Drawdown Distance.  Instead you define two piez lines.  The first is the full level, the second is the empty level.  (Careful!  In 7.03 it’s important that the full is piez line #1 and the empty is line #2.  Switch them around and you’ll get weird answers.)

This time there are three steps to take:

1. In KeyIn Analyses, select the “Staged Rapid Drawdown” option on the Settings tab.

2. Use Draw Pore-Water Pressure to draw the “full” piezometric line.

3. Use Draw Pore-Water Pressure again to draw the “empty” piezometric line.

Version 7.10

Version 7.10 does not change much from 7.03.  The only difference is that it’s no longer important in what order you draw your piez lines, so long as you have exactly two.  The higher of the two will be the “full” level, and the lower will be the “empty” level.

Further Reading

Several examples of staged rapid drawdown ship with GeoStudio.  If you have version 7.1 and you’ve installed the Resource CD you’ll get five matches if you search the examples for the keywords “staged rapid drawdown”.  Read the PDF with the “Rapid Drawdown With Multi-stage” example for a description of how staged rapid drawdown is implemented.

If you don’t have 7.1 but you’ve installed the examples distributed with earlier versions, look in the slopew folder for files with “drawdown” in the name.  (There may be one named “rapid drawdown with multi-stage.gsz”, but we also may have renamed it so I can’t be sure.)

Last week I started talking about some of the changes to the start page introduced with version 7.1, but I ran out of time to describe what was really the only new feature: searching examples and movies.

Resource CD 

The “Resource CD” is a new CD we’ve started shipping along with the software CD for anyone purchasing GeoStudio 2007 version 7.1 or later.  It installs a bunch of useful material to demonstrate how certain featuers of the software can be used, plus things like closed-form solutions to prove to the wary engineer that we really do solve things correctly!

The Resource CD is also available as a download from our web site, but it’s 512 MB so I don’t really expect many of you will bother.  It can be a very useful resource though!  So if 512 MB scares you, please email us and we’ll be happy to mail you the CD.

The examples and tutorial movies sections on the new start page provide access to resources you have to install separately.  If the Resource CD is not installed, these sections will ask you to install it.

Tutorial Movies  

The tutorial movies section links to movies for each product.  Each movie is 15-20 minutes long.  During that time you create a new problem, solve it, and look at the results.

Notice that there is a link to “Read the pdf” as well as one for “Watch the movie”.  The PDF is simply a transcript of the movie.  If your English isn’t great and you have trouble keeping up with the movie, it may be helpful to follow along on the script.

Examples

We’ve been shipping examples with our software for ages–probably since version 1 but I wasn’t here then so I can’t say for sure. 

But often customers didn’t even know they had the examples, because they were buried deep on the hard drive somewhere.  Even if you did know about them, it was hard to know which ones to look at, what they were supposed to demonstrate, or to understand why they did things in a certain way.  Many customers complained that the examples were too simplistic and didn’t reflect real-world scenarios.

With version 7 (even 7.00) we’ve really put a lot of effort into trying to make the examples more useful.

• We ship more examples, covering a wider variety of engineering scenarios.
• Most examples now also have a pdf describing the purpose, theory and the thinking behind the model.
• Some examples include movies generated by GeoStudio to show the results.
• And most important:  the examples tab gives you easy access to all the examples.

The examples tab on the start page lets you search the examples by keywords.  Type in a keyword or two and click Search, and GeoStudio will look for those words in the pdf’s and the gsz’s and give you a list of matches.

Searching for “rapid drawdown”, for example, has returned seven matches.  Each match is displayed with a short description, a link to the gsz, and in most cases a link to a pdf.  Click “Open the gsz” to open the example in a new window.

You can search examples even when you already have a file open.  Just switch to the Start Page by clicking the GeoStudio icon in the toolbar (or choosing Windows - Start Page from the menu), then click the Examples link in the top right of the page.

One engineer told me he regularly searches the examples while he’s working on his own problem.  As he comes to a point where he needs to add some new detail, he’ll do a quick search for an example that demonstrates that feature.

We’ve put a lot of effort into making these examples useful and available, and we’re committed to continuing that effort.  Expect to see new examples added to the list regularly and better search tools.

Do you use the examples regularly?  Leave a comment to let me know if the examples in the past have been something you’ve found useful or not.

The most obvious difference you’ll see when you first run version 7.1 is a redesigned start page.

• A: Click “New” to create a new file.  You can choose to create from a template or start with an analysis of a particular kind.
• B: Click “Open” to open an existing file.  You can browse for one on your hard drive, or pick from among your most recent files.
• C: Search documentation, example files, or watch a tutorial movie.
• D: Important notices are displayed in “info bars” at the bottom of the screen.

While many of the changes to the start page are purely cosmetic, there are some functionality changes that are worth mentioning.

Default Actions

Save yourself some wrist motion by double-clicking the “New” or “Open” tabs.  Double-clicking is the same as clicking that tab’s default item. 

So double-clicking New will create a new project from a template; double-clicking Open will bring up the standard File Open box to pick a file.

Documentation

You can think of the “Search” tab as a “Resource” tab.  It provides access to resources to help you better use GeoStudio.

The documentation section links you to the User’s Guide (aka Online Help)–though you can also just hit F1 at any point to get to the same thing.  This section also has links to the full text of the engineering books.  The User’s Guide tells you briefly what different controls do, where to click, etc.  The engineering books tell you how to model and explain the inner workings.

Examples and Tutorial Movies

Arguably the most important changes to the start page are the examples and tutorial movies sections on the Search tab.  But they’re also bigger topics which I’d like to address separately.  You’ll have to wait for the next installment!

News and Alerts

Certain alerts that used to appear scattered across the start page will now show up at the bottom in a yellow “info bar”.

Besides the news items (which by the way can be disabled completely using Tools - Options), you will also occasionally see alerts letting you know a new license file has been installed automatically, a new version of GeoStudio is available, or that a license on your computer is expiring.

Notice the little ‘x’.  Any alert that you don’t want to see anymore can be hidden by clicking the ‘x’.

With a File Open

When a file is open, the start page changes.  Instead of controls that let you open or create files, you’ll see a summary of the current file:

• A: Displays the name of the person who first created this file.  Click the “Author” title to edit it.
• B: A short description of the file.  Click the “Comments” title to edit it.
• C: A thumbnail of the last analysis you were looking at.
• D: A list of all the analyses in the file.  Click an analysis to jump to it, or the “Analyses” title to jump to KeyIn Analyses.
• E: Search documentation, examples and tutorial movies even while a file is open.

Next week I’ll describe the new Resource CD and dig deeper into searching examples and viewing the tutorial movies.

The Draw Contours command got a big makeover in version 7.1.  There are two major changes to contours:  saved contours, and contours in Define.

Saved Contours

I’ve mentioned before that version 7 introduced the ability to save graphs, so you don’t have to keep changing the parameters and re-selecting nodes as you explore different aspects of an analysis’ results.

Now Draw Contours gets the same functionality: saved contours.

The basic functionality is the same–pick your parameters, ranges and shading options–but now all those properties are saved and given a name, and a simple click on another saved contour in the list will update your drawing.

Contour Toolbar

To simplifiy it more, we’ve also added a Contour Toolbar.  After using Draw Contours to save the contours you want, you can switch between them right from the toolbar.

Contours in Define

Until now the Draw Contours command has always been a way of looking at the results, at the computed data.

With version 7.1, Draw Contours also shows up in the menu in Define, and lets you plot contours of the definition data.

Here’s a SLOPE/W analysis in Define view, showing the pore water pressures it got from its parent analysis.

This is a very powerful tool to help you determine if you have properly defined an analysis before solving it.  Besides contouring things like pore water pressure, you can also contour material properties such as C and Phi.

This week I’ll explore one of the new features introduced in version 7.1:  “transient” analyses in SLOPE/W.

In Theory

The theory behind transient stability analyses is fairly simple.  In the past a SLOPE/W analysis has calculated a factor of safety for a specific snapshot in time.  You determined what that snapshot was by identifying a SEEP/W analysis (for example) and a time step to use for the pore water pressure conditions.

A transient stability analysis simply performs the same calculations over and over at several successive snapshots in time.

In Practice

To perform a single stability analysis (at a single point in time) you have always been able to use KeyIn Analyses to pick another analysis from which to obtain pore water pressures or stress conditions.  In the past you had to identify the other analysis and the time step to use.  The stability analysis would give you a factor of safety for that snapshot in time.

Now you can choose “(all)” as the time step.

When you choose “(all)”, the SLOPE/W solver will repeat its calculations once for each time step it finds in the other analysis.  You end up with one factor of safety for each slice in time.

That’s it!  That’s all it takes to set up a transient stability analysis.

The fun of course starts when you can look at the results. 

Snapshots

The simplest way to look at results is just to pick a specific snapshot in time, a specific time step, and use SLOPE/W CONTOUR as you normally would. 

You pick the time step from the Analysis toolbar.

If the Time dropdown list has the focus (you can press Alt-I to give it the focus) you can use the Up and Down arrow keys to step through each time step.  You can watch how the critical slip surface and factor of safety change over time.

All the other features of SLOPE/W CONTOUR will work too, like drawing graphs, viewing slice forces, etc.  They all show you data for the current time step.

Graphing FOS over Time

To get the bigger picture, you can graph factor of safety over time. 

This graph is NOT under Draw Graph as you might expect.  Because you also need to select which slip surface to use, you find this graph under Draw Slip Surfaces.

There are two graphs to choose from.

The “Factor of Safety vs Time” graph uses the current slip surface, showing its FOS at each time step.  Use this graph if you care about a specific mode of failure.

The “Minimum Factor of Safety vs Time” graph ignores the current slip surface, instead showing the FOS of the most critical slip surface at each time step.  This graph is useful to see if a slope will be stable over time, at any slip surface.

Sometimes the two graphs will be the same (especially if you’re using the Auto-Locate method or the “optimized” slip surface option, because those are by definition the most critical), but if PWP conditions vary enough over time that at a particular step the critical slip surface is at a different location than at another step, the graphs will be different.

If you are doing a Probability analysis, you will also be able to see graphs of “Probability of Failure vs Time” and “Maximum Probability of Failure vs Time”.

Animation

As with any of the FE products, you can use the View Movie command to create a movie of the slope analysis.  Each time step becomes a frame in the movie. 

Next Week

Next week I’ll look at another new feature of 7.1.  Drop me an email or leave a comment if you are especially interested in one of them.

I’m happy to be able to break the news that we’ve released a new update to GeoStudio 2007: version 7.1.  We released version 7.03 back in September, but have not been idle in the seven months since.

Version 7.1, in a way, is what we really wanted version 7 to be.  Many features we had originally slated to release with 7.00 had to be cut because of time constraints, but are now finally done.

There are also several important new features in 7.1 that we never dreamed of originally, but that came about because of feedback from you and other customers who tried 7.00 and told us “it’s nice, but it doesn’t do …”.

As usual, 7.1 is a free upgrade if you already have a version 7 license.  Prices for new licenses and upgrades from version 6 are on our web site.

New Features in 7.1

I’m going to take the next few weeks to walk through some of the new features.  You can read the full list of changes in the Release History, but I warn you, it’s long!  (And rather dry reading.)

Here’s a list of the more interesting changes.  I’m not sure yet which ones I’ll talk about–if any catches your eye, let me know and I’ll make sure to go into it in more detail.

• A new Spatial Mohr Coulomb material model in SLOPE/W lets you vary material properties as a function of x and y.  The FE products similarly include spatial functions for applying initial conditions (vary initial temperature across a material, for example).
• Ponded water weight is calculated automatically, and we’ve got much better visual feedback to show you how the weight is being applied.
• SLOPE/W can do transient stability analyses.  Gives you a factor of safety for each time step, graph FOS vs time, etc.
• You can use Draw Contours even in Define now, to visualize the data Solve is going to use as input.
• Install a new Resource CD and do a keyword search through all the resources to quickly find an example that will demonstrate a concept you need to learn.
• You get thumbnails of your gsz files!
• Generate a report from any product.  (In 7.0 this feature was only in SLOPE/W.)
• Save a list of contours, much like you can save a list of graphs.
• Display Sketch Text in only one analysis.

That should be enough to whet your appetite, and keep me going for a few more weeks!

Compatibility Caveat

Because of some rather important changes to the file format to allow for these new features, you may have trouble using the older 7.0x version to open files saved with 7.1.  If you have several people in your office, I’d suggest everyone upgrade to 7.1 at the same time.

Free Download

Click here to go to the Downloads page, then click “GeoStudio 2007 v7.10, Installer“.  As always you can try it out for free using the included Viewer or Basic license. 

If you already have an older version of GeoStudio 2007 installed (e.g., 7.03), uninstall that one first, then install this.  (Don’t worry, you won’t lose any existing settings.)