NAVFAC DM 7.2: Verification Examples, Some Parting Observations, and an Announcement About DM 7.1

At the end of NAVFAC DM 7.2 is a series of example problems which include the following:

Although the inclusion of these is “obvious,” some background is in order.

When the original DM 7.01 and 7.02 were introduced, examples were scattered throughout the books, and were of variable quality, generally not very detailed. Combined with the terse (and sometimes cryptic) guidance, the lack of detailed examples made them difficult to use in an academic setting for something other than a supplement, and including more examples would have made the concepts clearer.

DM 7.01 and 7.02 came at the end of a fruitful period of knowledge expansion in geotechnical engineering, but even towards the end of the 1980’s things were happening (many documented in NAVFAC DM 7.2) that really begged for an update. With the pedagogical deficiencies noted earlier, a comprehensive teaching document was needed to educate engineers and other practitioners in the science of geotechnical engineering, and that came forth in the Soils and Foundations Reference Manual. Although many of the facts (and figures, albeit redrawn) came from DM 7.01 and 7.02, the book was structured for an educational setting, complete with worked examples (which you can see now in NAVFAC DM 7.2.) Although it was intended primarily for short courses, it could be used for undergraduate students, and (with supplements) I used it in both my Soil Mechanics and Foundation Design and Analysis courses.

It is my hope that the FHWA will revise the nearly twenty year old Soils and Foundations Reference Manual, which is complementary to these new DM 7 documents.

An Announcement About DM 7.1

This site was quick to publish NAVFAC DM 7.1 when it came out in 2022, and it has been a success. There were a few typos and places where revision was needed, and about the time NAVFAC DM 7.2 came out Change 1 to NAVFAC DM 7.1 was also released. That Change was incorporated into the print document and can now be ordered. Whether you never bought NAVFAC DM 7.1 before or just want a corrected copy, it’s available both from the publisher and now in distribution, so you can order it in places such as amazon.com.

Some Parting Observations

The whole DM 7 project, including both NAVFAC DM 7.1 and NAVFAC DM 7.2, was a monumental task. While I voiced my objections about many things, most of these were about the state of geotechnical practice and how it can be improved. As books which document the state of the practice, NAVFAC DM 7.1 and NAVFAC DM 7.2 will become necessary references.

With many thanks to the authors and all of those who worked on these books, just one thing: don’t wait so long to update it…