New Look to the Blog

by Nate Hekman on September 12, 2008

In an attempt to make this blog be more useful, I’ve updated the layout, hoping to make it easier to find what you need.

One change in particular I’d like to point out:

  • The Categories have been rearranged, around commands, objects or concepts in the software.  That should help you if you don’t follow the blog regularly, or you only ran across it recently.  If you’re struggling to understand functions you can click on the Functions category and immediately see everything I’ve written about functions.

Summer is definitely over here in Calgary, with temperatures dipping and leaves changing colour.  When our workshop is over next week I will be getting back into serious blogging mode again and try to bring you a new tip every week.

As always, if you have comments, suggestions or questions, please leave a comment or email me.

Nate

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summer holidays

by Nate Hekman on August 26, 2008

Gentle Readers,

I hope your summers have been going well (or your winter–do I have any readers from the southern hemisphere?).  This summer we’ve enjoyed beautiful weather here in Calgary, which has allowed me to rack up 800 km on my bike commuting to work.  Woohoo!

I’m going to take a short blogging break.  Grokking GeoStudio will be on holidays for the next couple of weeks, but I’ll be back in time to celebrate Grokking’s first anniversary, September 19th!

Will any of you be attending our annual workshop in Banff this year?  September 15-18.  Look me up, I’d love to chat with you face to face.  If you haven’t signed up yet you’ll have to wait for next year–the workshop is full and the waiting list already a mile long.

Enjoy the rest of your summer, and look for me again in September.

Nate

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demystifying viewer, student and basic licenses

by Nate Hekman on August 19, 2008

We have a love-hate relationship with FLEXlm, the licensing utility that is responsible for those USB dongles you have to plug in before you can run GeoStudio. 

On the one hand it’s annoying to have that dongle to keep track of, and a big pain if the automatic license renewal doesn’t work for some reason.  But the nicer side is that it allows you to buy different types of licenses to better fit the way you want to use the software.

Even if you already own a full license, some of the other license types may still be useful to your office.

Viewer License

The Viewer license is free and is included automatically with every installation.  It gives you access to every feature of the software except two: saving and solving.

It’s great as an evaluation tool before buying a new product. 

It’s also great for your manager who needs to review your work but doesn’t do the modeling himself.  He can open your file, look at all the definition data, explore the results using graphs, contours, exporting data to Excel if necessary, all the tools the software provides.  All without spending any money on a license.

Student License

The Student license is also free, and also included in every installation.  It is a very “lite” version of the software, intended to help people learn geotechnical engineering concepts, not to perform real engineering analysis.

You can save and solve, but you are restricted to a small mesh, a small number of regions, and so on.

The Student license is most useful as a teaching aid for undergraduate engineering classes.

Basic License

Basic licenses are the most inexpensive licenses we sell–two different options for $995 each. 

Like the Student license, they limit access to some of the more advanced features, but are much more powerful than the Student license, and definitely powerful enough to use on the more routine geotech problems you’ll encounter.

There are two Basic licenses in the latest version:

  • VADOSE/W Basic is a 1-D version of VADOSE/W and CTRAN/W.
  • GeoStudio Basic is a single license that gives you access to all the products except VADOSE/W.  So for a low price you get SLOPE/W, SEEP/W, SIGMA/W, QUAKE/W, TEMP/W, CTRAN/W and AIR/W.

If your firm tends to do more routine analyses, you may want to consider the Basic license.

Full License

The full license, of course, gives you access to all the features of a particular product.

Picking Your License

You choose between those four types of license from the Start Page, before opening or creating a file.  In the most recent version the options look like this:

In version 6 (GeoStudio 2004) they look like this:

More Information

You can read more online about GeoStudio Basic, VADOSE/W Basic and the Student Edition.  The GeoStudio 2007 Product Details brochure shows which features are limited in the lite versions.

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more template tips

by Nate Hekman on August 11, 2008

While we’re on the topic of templates, here are a few more tips to use them effectively.

Default template

Choose File – New, select a template, then click “Make this the default template” if you want to use this template all the time.

The default template will be used any time you start a new file by clicking the “New File” button in the toolbar, or by clicking one of the product icons on the Start Page.

The default template should also be the one that is selected initially when you choose File – New from the menu (though that appears to be broken in the current version–I’m hoping we can fix it in the next release).

Creating a New File From the Menu, Toolbar or Start Page

As I alluded to, there are several ways to create a new file, and they all work a bit differently.

  • Choosing File – New from the menu always shows the box where you get to choose a template, followed by the KeyIn Analyses box.  Since the default templates we ship do not contain any analyses, the KeyIn Analyses box is initially empty.  If your template does have one or more analyses in it, they will show up in KeyIn Analyses.
  • Choosing the “New File” button from the toolbar uses the default template.  The result is as if you used the menu item, clicked “Create from this template”, selected the default template, then clicked Create.
  • Clicking one of the product icons on the Start Page (next to the “New” tab) uses the default template and creates a new analysis.  The result is as if you clicked the “New File” toolbar button, then created an analysis.  So if your default template already has one analysis, you’ll end up with two (the template one and the new one).

Create From Existing

You can use any existing .gsz file as if it were a template.  Choose File – New from the menu, then click the “Create From Existing…” button and choose a .gsz. 

The .gsz file gets opened but has no name, so when you try to save it you get prompted for a new file name.

The Location of the Templates Folder

The templates listed when you choose File – New are all .gsz files from your Templates folder.  The location of the Templates folder can be changed in Tools – Options.  One reason you may want to change the location is to share templates with others in the same company–you could create a Templates folder on a shared location on the network.

No Analyses

You may want to create a template with no analyses in it, like the ones that ship with the software.  That’s handy if you don’t know what analyses will be used, but you want to set up some common defaults, like default boundary conditions, materials, or units.

To create a template with no analyses, you start out (unintuitively) by creating all the analyses you could possibly want (e.g., one SLOPE/W, one SEEP/W, etc.).  That gives you the framework in which you can define the appropriate boundary conditions, materials, and so on.  Don’t set any analysis-specific properties like time steps (because our next step is going to be to delete the analyses); only create global objects.

Now delete all the analyses you created.  The global objects (boundary conditions, materials) and the file-specific settings (units, scale, extents) will remain, but when you start a new file with this template you’ll have no analyses.  As soon as you add an analysis, you’ll see the global objects that apply to it.

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templates

by Nate Hekman on August 5, 2008

Most of us should be familiar with templates.  We use them every time we create a fax cover sheet in Word.  A Word template is really just a regular Word document but with a different file extension, to avoid repeatedly setting up the same standard titles and styles and boxes.

GeoStudio 2007 ships with two templates, and lets you create your own as well.  One of the templates it ships with is a blank document with imperial units already selected (feet, seconds, pounds, etc; under Set Units & Scale); the other is identical except with SI units (meters, seconds, kN, kPa, grams, etc).

In many cases you could benefit by creating your own templates:

  • If you find yourself always going back into Set Units & Scale and making the same changes.
  • If you use a different page size (under Set Page). 
  • If you often want to start with a SLOPE/W analysis already created.
  • If you want everyone in your office to have a standard format with your company name / logo / etc at the bottom of the page.
  • If you find yourself using the same boundary condition over and over.
  • Any other repetitive changes you make.

A GeoStudio template is really just a plain old .gsz file saved in a special folder, so anything that normally gets saved in the .gsz can be saved in a template.

Let’s create a simple template today just to demonstrate how it’s done.  Say I find myself often doing stability analyses, so I want to just open a template that already has a SLOPE/W analysis, but I always use the Entry and Exit slip surface option instead of Grid and Radius, and I always want to store 10 critical slip surfaces rather than the default of 1.

1. Create a New File

You start just the same as if you were creating a new file.  In fact you may want to just take one of your existing files to use as a template.

2. Set Things Up

Remember a template is just another .gsz file, so you set things up just as if you were creating a normal analysis.  In my case I’m going to:

  • Use KeyIn Analyses to add a SLOPE/W Analysis.
  • On the Slip Surface tab, change the Slip Surface Option to “Entry and Exit”.
  • On the same tab, change the “No. of critical slip surfaces to store” to “10″.

If I wanted, I could create some common materials I always use, change my page size, problem extents, scale; I could create other analyses, draw a couple of regions, even assign materials to those regions.

3. Give It a Comment

In KeyIn Analyses, select the root item in the tree (labeled “(untitled)”), then describe the template in the Comments field.  This description will show up later when you try to use the template (we’ll try that in a minute).

I’ll write “Entry and Exit slope analysis that stores 10 critical slip surface.”

4. Save As Template

This is the step that differentiates this from a normal file.  Chose File – Save As Template, and give your template a name, such as “Entry and Exit Slope”

5. Use It

When you want to create a new file from this template, choose File – New, and your template will show up in the list.  Notice that when you click on it, the comment you typed at step 3 is displayed to remind you what this template is about. 

More Tips

Next week I’ll describe some more concepts around templates.  In the meantime, I’d really like to hear how you use templates.  Is it something you’ve explored?  Do you use them regularly?  Did you not even know they were there?  Leave your comments or questions and I’ll address them next week as well.

 

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In an earlier comment on transient stability analyses, Ong said:

We (engineer) face a problem when we want to define the soil-water characteristic curve.  We have no idea what is the maximum suction can develop during the time of analysis, so we normally give up.

I asked Lori, one of our support engineers, if she could address this problem.  Lori says:

It’s important to understand that you only need to define the soil-water characteristic curve (also known as the volumetric water content or VWC function) if you are doing a transient analysis.   The VWC  function describes how water is stored or released due to changes in matric suction or negative pore-water pressure during the transient process.    

 

However, once you have a VWC  function defined, you can also use it to estimate the hydraulic conductivity function using established estimation techniques that are built into the GeoStudio software.  The hydraulic conductivity function is required for both a steady-state and transient analysis, so often a VWC function is defined regardless of the type of analysis that is being solved.

 

It’s true that if you expect the negative pore-water pressures to reach a particular value, then the function needs to at least be defined up to this value.  However there is a rule of thumb that you can use to determine what this value might be.   Unless you are considering evaporation and using a negative flux boundary condition at the ground surface, the maximum negative pore-water pressure that will develop above the phreatic surface will be hydrostatically negative.   

 

To estimate hydrostatic pressures above the phreatic surface, take the maximum distance between the ground surface and the anticipated phreatic surface or P = 0 contour, and multiply it by the unit weight of water (9.807 kN/m^3 or 62.4 pcf). 

 

So if the maximum distance between the phreatic surface and the ground is 10 m, then the maximum negative pressure that would develop  would be approximately 100 kPa. 

 

Please note that if you are going to use the volumetric water content function to estimate the hydraulic conductivity function, you will need to ensure that it has been fully defined, from saturation through to residual water content. 

 

There is no problem with defining the water content function over a range that is larger than the anticipated computed negative pore-water pressures.  Just make sure you have defined a smooth function that has a nicely defined air-entry value and a smooth transition to a residual water content if necessary.  

 

Within the GeoStudio software, you can estimate the volumetric water content  function using grain-size data, so you may be interested in watching the movie on function estimation that is available on our website at http://www.geo-slope.com/support/geostudio2007/tutorials.aspx?id=SepFnEstMov.

Does this help?  Please respond with your own comments or questions!

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manually editing field names in sketch text

by Nate Hekman on July 14, 2008

If you find yourself clicking the “Insert field…” button in Sketch Text several dozen times a day, you may be unaware of a convenient shortcut.

Let’s say, for example, you have several anchors and you want to display the bond length, spacing, resistance and capacity for each.  That’s four visits to the “Insert field” dialog box for each anchor.  Carpal tunnel problems are not far behind.

To simplify the task, just use Insert field to insert the four fields for one of the anchors.

Then select everything in the box (Ctrl-A), copy it to the clipboard (Ctrl-C), and paste it back in again (Ctrl-V).

Now you need to edit the second group.  See where it says “Reinforcements[1]“?  You need to change that “1″ to a “2″.  Instead of clicking on it (which just puts you back in the Insert field box), hold down the Ctrl key while you click.  That will position your cursor where you click, so you can now edit the text.  (Or you can use the arrow keys to move your cursor into the field name.)

Do the same for any additional anchors, and click on your drawing to position the text just as you normally would.

[Note:  While I was trying this out for this blog, I noticed the fields did not always show up as blue underlined text.  Normally that would indicate they are not valid fields, but in this case it appears to be a bug.  When you insert the text on your drawing, all the fields are interpreted correctly.  There's just something strange going on in the edit box itself.  Guess I'd better get back to programming!]

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file properties

by Nate Hekman on July 8, 2008

Some of our customers (maybe all? I’m not sure how common this is) keep a huge number of gsz files on their computers. 

They may have a large team of people all sharing access to the same files.  They save a dozen copies of an analysis, each with a slight difference from the others.  One customer described to us how his team uses spreadsheets to keep track of all these files, the differences between them, and who last edited any particular file.

Even if your office doesn’t go to that extreme, you’ll likely still find it useful to store additional information about your analyses that you can refer back to later, or that your manager or co-worker can access to understand what you were trying to do with a particular analysis.

The place to write up those comments is in the file properties.

Use the KeyIn Analyses command, then click on the very root item in the tree, the one that (typically) has the same name as the file.

You’ll notice there’s room there to type in a title, an author (so people know who to go to with questions), and comments.  This is where I find it useful to write a short description of the overall project, what I’m trying to achieve with this .gsz file.

You can also write comments for each individual analysis.  Still in KeyIn Analyses, click on an analysis in the tree.

At the top-right is a Description field.  I use it to describe the purpose of this specific analysis.  Often it isn’t really needed–if I have two SEEP/W analyses, the first one steady-state and the second one transient, it’s pretty obvious what I’m doing.  But if I have ten SLOPE/W analyses, each identical except for the value of C, the Description field comes in really handy.

When writing comments, it’s best to imagine yourself coming back to this file in a year or two, and having to remember what it is you were doing.

All of those comment fields are visible from the Start Page.  Click back on the root item in KeyIn Analyses and then close the dialog box to see the Start Page summarizing the entire file.

If you save the file while you’re at the Start Page, then next time you open it you’ll be put back at the Start Page to quickly see what the file is about.

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international geotechnical blogs

by Nate Hekman on June 30, 2008

I’ve been using Google lately to find what sites are linking to ours, and in the process ran across some non-North-American geotech blogs.  Some I can only read with the help of Babelfish, so no guarantees about content, but you might find them interesting!

I was also surprised (not sure I should have been) to find that some of the largest referrers to geo-slope.com are some non-English engineering forums, such as:

Our office is rather quiet this week, with school out for the summer, Canada Day tomorrow, and the Calgary Stampede beginning on Friday.

I’ll try to bring you something of more substance next week!

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finding help when you need it

by Nate Hekman on June 23, 2008

Even with software as dead-simple to use as GeoStudio ;-) there will be times you need some help knowing how to get something accomplished.

Engineering Books

For a discussion of the theory behind the software, refer to the engineering books.

Each of the eight products (SLOPE/W, SIGMA/W, SEEP/W, etc) has its own book, with over a dozen chapters discussing everything from how to model, to practical modeling tips, to meshing, material properties, boundary conditions, analysis types, interpreting results, and more.

You received a hardcopy of the engineering books at the time the software was delivered to you, but the books are also installed on your computer as PDFs–you can access them from GeoStudio’s Start Page.

The engineering books were updated when we released version 7.1 since that release included many new features.  If you bought GeoStudio 2007 before April 2008 then those new features will not be included in the hardcopy book you have.  However, the books are also installed on your computer as PDFs, and those were updated at the same time you updated your software.

Online Help

The online help is the help window that pops up if you hit F1 in GeoStudio.  From anywhere in the software you can hit F1 to display a help topic describing the current mode, command, or dialog box. 

So what’s the difference between the engineering books and the online help?  I like to sum it up with this:

  • The engineering books help you understand how to model using GeoStudio.
  • The online help tells you what buttons to press and what numbers to fill in.

We very consciously chose not to write about the theory in the online help, or to write about specific dialog boxes or mouse clicks in the engineering books.  This makes the books an invaluable resource and educational tool even as the software continues to change from version to version, and keeps the online help as a lightweight quick reference. 

Examples

If you’re looking for an example on how to model a certain type of problem, search through our examples online.  We have hundreds of analyses available demonstrating various features, along with PDFs describing the approach.

For example, searching for “rapid drawdown” (go ahead, click the link to see the search results) gives me seven matches.  The fourth one down combines SLOPE/W and SIGMA/W using effective stress, which–what luck!–is just what I’m trying to do.  First I’ll read the PDF to see if it’s worth downloading:

Rapid Drawdown with Effective Stress.pdf

The PDF is eight pages long, with descriptive text, diagrams, figures and equations.  Perhaps it’s all I need to understand how to approach my own problem, or I can download the Gsz file right from the web site:

Rapid Drawdown with Effecive Stress.gsz

Movies

Tutorial movies are especially useful if you are new to a product.  In under twenty minutes (most of the time) the movie will walk you through creating a new analysis, defining the geometry, assigning materials and boundary conditions, solving, and looking at the results.

We currently have one movie per product.  If you’ve installed the Resource CD they are available from the GeoStudio Start Page.  They’re also on the web for everyone else.

The web site also has one additional movie (Function Estimation in SEEP/W 2007), and we hope to be adding more movies throughout the year.

Forums

I have found the Eng-Tips forums to be frequented by knowledgeable and experienced engineers.  Questions and answers are intelligent and professional, and there are often questions about how to model using a specific application, including SLOPE/W or other GEO-SLOPE products.

So if you have questions that aren’t answered in the engineering books or online help, you may want to consult your peers at one of these Eng-Tips forums:

Technical Support

Of course you can always email our support engineers.  We are very proud of the reputation we’ve gained for friendly expert support.  The Support section of our web page describes how to contact us.

 

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