This is an archived newsletter. Click to learn what RetainPro can do for you..

Summer 2007
Dear Colleague:

Only a few days of summer remain until Labor Day finale. I hope you made time to enjoy the things on your summer "to do" list: swimming, camping, hiking, fishing, gardening, sun bathing, whitewater rafting, boating, reading, traveling, rock climbing... Didn't do all you planned? Well, there's always next summer...

About these newsletters

For those of you who are new users, these quarterly newsletters keep you updated on what we are doing, and discuss technical issues related to retaining wall design. If you missed a previous newsletter, they are all posted on our home page. In them you'll find important technical issues and we urge you to read them.

Is AutoUpdate keeping you current?

AutoUpdate is a valuable new feature to keep you up-to-date on any revisions we make. The latest update is Retain Pro 2007E, released August 9th, This has important improvements to the segmental wall option, and adds an option to enter a different soil density on either side of the wall. This is particularly important when retaining water on the heel side. If you don't have this release, just click YES when asked if you want to check for updates. You can also download it from This is for version 2007 users only, and you will need your email address, password, and PAC By the way, if you can't find your PAC (Product Activation Code) you can retrieve it on our support page.

Still using version 2005 or earlier?

You're missing many valuable new features, such as updating to IBC '06 and MSJC '05, segmental retaining wall design, pier foundation option, masonry option to use LRFD, the Equation Menu, new user's manual with more design examples, AutoUpdate feature, and other improvements. For a list of all features in Retain Pro 2007 visit Upgrade discounts begin at $195, and until October 31st includes the new 7th edition of Basics of Retaining Wall Design. And remember that you can download the program immediately after ordering - no more waiting. For features, a demo, and ordering click

Survey Results

We had a great response to our online Retain Pro 2007 User Survey! It is only through your feedback that we know how we're doing -- and how we can do it better.

Here are some results from the survey (version 2007 users):

Surprise to us: Nearly half of you (47%) are small one- and two-persons firms!
Companies with over 100 technical employees: 2.6%
Using Windows XP: 88%; Vista: 6%; Windows 2000 or "other": 6%.
Design over a dozen retaining walls per year: 47%
Users who also have ENERCALC: 36%
Top five features used: Cantilevered walls, restrained walls, seismic design, gravity walls, segmental walls.
Users who asked for technical support: 53%.
And 89% gave us an overall rating of either "Excellent" or "Very good".
We also got many good suggestions for things to improve or features to add.
Our thanks to all who participated!

Technical issues

California projects
On January 1st California switches from the time-worn UBC '97 to IBC '06. The 2007 California Building Code (CBC '07) is now out - just received my copy ($247, ouch!). Except for amendments applicable to public buildings such as schools, hospitals, fire stations, libraries, etc., it is the same as IBC '06.

Windows Vista®
It's hard to buy a new computer now without Vista installed. Our recent survey indicated about 6% of you are now using Vista. So far we have had no reports of problems, and one of our programmers installed Vista and reports that Retain Pro runs fine. If you do have a problem or comment, please post a note on our User's Forum (access from Home page).

Retaining water
When designing a wall to retain water (or other liquid) enter it's density and active pressure (both are the same for a liquid) on the heel side, and soil active pressure and density on the toe side. Both these entries are available on the Criteria screen (release 2007-E only). Also remember that if the liquid can penetrate below the footing you can't use the weight of liquid on the heel for overturning resistance since liquid pressure under the heel will cancel the downward pressure. For this case enter zero for density on the heel side and adjust the footing weight for buoyancy affect.

Seismic kh factor
This is the acceleration factor used in the Mononobe-Okabe equation for seismic forces on cantilevered retaining walls. The NEHRP Commentary recommends a value of kh = SDS / 2.5, however it is the general consensus that kh can be taken as one-half the peak ground acceleration. Remember that you can look up your seismic data based upon zip code or latitude/longitude by using TechLinks, accessible from our home page.

The new Equation Menu

Have you noticed the Σ sigma icon on the toolbar? It offers quick-solving a dozen complex equations relating to retaining walls (such as the Coulomb and Rankine equations). Just enter the variables and the result is instant. It's quick and easy. Use it for checking or for independent applications. More equations will be added.

Suggestions and comments.

We want to hear from you. Email me at

With best wishes,


Hugh Brooks, SE
Retain Pro Software

PS: REMEMBER: The new 7th edition of Basics of Retaining Wall Design is free with all orders until October 31st!

NOTE: If you received this Newsletter and you are not the person in your organization who should receive it, please forward it to the appropriate person and ask him/her to go to and change to the correct email address.

Retain Pro Software div. HBA Publications, Inc. PO Box 826 Corona del Mar CA 92626 949-721-4099
© 2007 HBA Publications, Inc. All Rights Reserved.