The “Before and After” of NAVFAC DM 7

It’s not an overstatement to say that NAVFAC DM 7.01 (Soil Mechanics) and DM 7.02 (Foundations and Earth Structures) are the two most consequential documents on geotechnical engineering to be produced in the last century, and remain that to this day. This is in spite of the fact that it is now a half century old. Sales of hard copies of DM 7.01 and DM 7.02 have supported this site for many years.

So what is the history of this document? And has NAVFAC (the Naval Facilities Engineering Command) updated it? This brief article seeks to answer that question by looking at the documents themselves. We don’t have “inside information” or history, but hopefully we can shed some light and give you an opportunity to look at the history of this important document.

What is a “DM” and the Original DM 7

The acronym (the military loves these) “DM” stands for “Design Manual. NAVFAC put out a series of documents to give guidance to designers and builders of facilities for the United States Navy. “DM-7” refers to the design manual for geotechnical engineering, entitled Soil Mechanics, Foundations and Earth Structures. The “original” DM-7 was issued in March 1971; the first change version dated September of that year can be downloaded here. Even it, however, was a successor to the “NAVDOCKS DM-7” dated February 1962 (you’ll see that reference in many older texts.)

From One to Three Documents

In 1982-3 the Navy opted to divide DM-7 into three parts:

DM-7.1, Soil Mechanics
DM-7.2, Foundations and Earth Structures
DM-7.3, Soil Dynamics, Deep Stabilization, and Special Geotechnical Construction. We do not have this document but we do have its successor, MIL-HDBK-1007/3, dated 15 November 1997.

The DM-7.01 and DM-7.02 documents we offer in print and download are minor revisions of those documents issued in 1986.

As J. Ledlie Klosky of the United States Military Academy noted in the preface to our version of DM-7.01:

This extraordinary document, published in 1982, is now considerably out‐of‐date and, except as UFC 30220‐10N, is no longer a sanctioned publication of the US Government. It is provided here as a reference because of the incredible density of highly practical geotechnical design guidance it contains. It is also of significant historical interest, and when combined with DM 7.2, it represents perhaps THE principle compendium of geotechnical knowledge used by designers between 1982 and around the turn of the century. It is a testament to the strength of the document that some of the design methods presented are still in use today. The importance of the Federal labs (particularly FHWA, Bureau of Reclamation, Army and Navy labs) in pushing the practice of geotechnical engineering forward between 1930 and around the time of the publication of this manual cannot be overstated, and this manual is a testament to that heritage. Thus, you are holding in your hands (or in your computer memory) a great reference for preliminary design guidance and a knowledge artifact that will be recognized by nearly every senior practicing geotechnical engineer.

It’s unlikely that the Navy had any idea that this document would be such a “hit” in the industry. That’s for a variety of reasons. One of them, as Klosky notes, is that it came at the end of a very fruitful era of research and advancement in geotechnical engineering, starting with pioneers such as Terzaghi, Casagrande, Taylor, Tschebotarioff, Spangler and many others, and supported both by military and civilian agencies of the United State government. Another is that, especially with the 1982/6 versions, the figures and text were largely free of copyright, which guaranteed that they ended up in just about every geotechnical text and reference book (including this one.)

In the late 1990’s the coming of the internet made widespread dissemination of information simple and economical. DM-7.01 and DM-7.02 became a part of that when the Navy put out an online version of this, which this site disseminated widely even through events such as 9/11 (when many military sites went “dark” even with information such as this) and the revisions we will discuss below. The scanning and OCR technology of the time were not up to what we have now, and so the version has a “long in the tooth” air about it, but in those years it helped to disseminate the valuable information contained in DM-7.

The Coming of UFC 3-220

Click on the image to order the combined volume of NAVFAC DM 7.01 and 7.02.

With a new millennium the needs of the military for construction guidance did not stand still, especially with the conflicts in Iraq and Afghanistan. Additionally the military worked to homogenize its guidance across the service branches, thus the Navy’s Design Manuals because part of the UFC (Unified Facilities Criteria) program. For geotechnical engineering this meant the UFC 3-220 series. Relating to the DM-7 series there were two rounds of revision, the first in 2004-5, and the second in 2012 with more recent revisions.

The 2004-5 Round:

Although Soil Mechanics was pretty much left alone, Foundations and Earth Structures was broken up into specific topics. This reflects the fact that, of the two major volumes, the second has aged more poorly than the first.

UFC 3-220-10N, Soil Mechanics. This is simply a “wrapper” for the old government version of DM 7.01.
UFC 3-220-01N, Geotechnical Engineering Procedures for Foundation Design of Buildings and Structures. This is (more or less) an update to DM-7.02, although some of the more specialised topics are dealt with elsewhere
UFC 3-220-01A, Deep Foundations. This is a wrapper for TI 818-02, which in turn superseded EI 02C097. It is one of the more comprehensive documents about deep foundations ever put out, although it had more than its share of technical problems in its publication.
UFC 3-222-02, Pile Driving Equipment. This is a wrapper for TI 818-03. This webmaster wrote about half of this document.
UFC 3-220-03FA, Soils and Geology Procedures for Foundation Design of Building and Other Structures (Except Hydraulic Structures)
UFC 3-220-04FA, Backfill for Subsurface Structures
UFC 3-220-06, Grouting Methods and Equipment
UFC 3-220-07, Foundations in Expansive Soils
UFC 3-220-08FA, Engineering Use of Geotextiles

The 2012 Round:

With this round the Navy decided to make their chief document a “front end” for the International Building Code. The document is UFC 3-220-01, Geotechnical Engineering, in this case Change 1 dated 3 November 2021.

Some Thoughts

It is unfortunate that, in adopting the IBC, the Navy has decided to leave behind a generation and more of reference materials which have enriched the geotechnical industry. But we have this legacy still available, and trust that is is helpful to you.

Update: they didn’t leave them behind after all. Right after this was posted, we learned that they had updated DM 7.01 and a direct update for DM 7.02 is in the works. You can read about this here and watch the video below for more information.