Tag Archives: Terzaghi and Peck

Happy Karl Terzaghi’s Birthday 2011!

Greetings to all Terzaghi fans!  Yes, it is that time of year again, where our thoughts turn to the anniversary of the birth of one of the greats in our field.

Last year I had a football themed post (college football, in case you were wondering…and that is American football for our fans outside the U.S.) since Terzaghi’s birthday was on a Saturday. Since I am not a big pro football fan, and since I used football last year, I figured I would do something different for this year’s weekend post.

The August 2011 edition of the International Society for Soil Mechanics and Geotechnical Engineering ISSMGE Bulletin is headlined with an article on the history of ISSMGE: “THE ISSMGE FROM 1936 TO 2011 A RETROSPECTIVE ON THE OCCASION OF THE 75TH PLATINUM JUBILEE ANNIVERSARY” by Kenji Ishihara and Michele Jamiolkowski. The Bulletin is in two parts at this link. The article is an outstanding work providing an excellent account of the start of ISSMGE as an international conference and its evolution into the ISSMGE we know today.

It should be no surprise that Prof. Terzaghi was very active and one of the key figures in the formation and success of ISSMGE, which began as the International Conference on Soil Mechanics and Foundation Engineering (ICSMFE). Many of the giants of soil mechanics and geotechnical engineering on which we base al of our work were instrumental in the start of ICSMFE and its impacts on our profession. As for that time in history (1936) and how it was important to our field:

The time had come to hold a Conference aimed at exchanging and sharing information on Earth and Foundation Engineering.

It was Professor Arthur Casagrande (assistant professor of Harvard University) who sensed the timing, conceived the idea and carried out the herculean task of running the conference all the way through, in his role of Secretary General, with K. Terzaghi (Professor of Technical University of Vienna and visiting Professor of Harvard University) as Chairman. Professor Peck once remarked “Our Society owes an enormous debt to Arthur Casagrande for his conviction that the time was right for the International Conference and to his tremendous efforts to organize it“.

Since the first ICMSFE was so successful, it became clear that the Conference should not remain a one-off event but should, instead, be continued within a few years, possibly being held in Holland where earthwork engineering is so crucial to the country.

It was also requested to set up a permanent international organization. Thus it was decided to establish International Committees consisting of National Committees with K. Terzaghi as President and A. Casagrande as Secretary. It was also decided that at the next Conference the International Committees would submit the draft of the Constitution and of the By-laws, which are essential for the Society to become a permanent organization.

There was at that time a widespread awareness that it was the moment to set up a common denominator institution that would group engineers with diverse backgrounds but involved in our discipline.

Portion of group photo from 1st ICSMFE, 1936.  (From ISSMGE Bulletin Vol 5, No 4, August 2011, p3)


Photo of Terzaghi addressing the opening session of the 4th ICSMFE, 1957.  (From ISSMGE Bulletin Vol 5, No 4, August 2011, p7)


And the rest, as the saying goes, is history!

As an editorial note on the first year, Ishihara and Jamiolkowski offer this observation:

It is commonly recognized that K. Terzaghi is the originator of modern soil mechanics and foundation engineering and therefore father of our profession. After tracing the history of development, the writers had a strong belief that this is true. Not only was he always a leading figure in the forefront, but he conveyed strong messages on the role and importance of the soil mechanics and foundation engineering every time he participated in the ICSMFE. We are very much impressed by his enthusiastic and heartfelt message to our community.

No less important was the role played by Arthur Casagrande. He was instrumental in persuading the President of Harvard University to host the conference and carrying out all arrangements for organizing the first International Conference on Soil Mechanics and Foundation Engineering. The great success of this conference contributed greatly for establishing the place of soil mechanics in engineering practice throughout the world. He also dedicated himself to the ISSMFE as the 3rd President between the periods of 1961 in Montreal to 1965 in Paris.

There is a saying that for a great religion to be established, there always are two key-role playing giants. For Christianity Jesus Christ is the originator and his disciple Saint Paul was the great evangelist. For Greek philosophy, Socrates was the great philosopher and it was Plato who was the greatest disciple. Terzaghi and Casagrande are considered as a combination in the same context. Without Terzaghi, Casagrande would not have been so well-known. Had there not been Casagrande, the fame of Terzaghi would have developed in a different format.

Now neither I nor the authors are suggesting that soil mechanics is a religion, but their point on the timing and combination of Terzaghi’s and Casagrande’s work was critical to what we see as the field of soil mechanics/geotechnical engineering today. Without these two and others seeing a need, taking charge, and filling that need, we could very well be viewing things from a completely different framework.

So as we reflect on this celebrated day, let’s remember not only Prof. Terzaghi’s great technical achievements, but also his role as a leader (along with many others) shaping our field of practice and our professional societies.

Happy Karl Terzaghi Birthday 2010


October 2nd, is the day we (or at least a lot of us geoprofessionals) have all been looking forward to all year – the birthday of Professor Karl Terzaghi, The Father of Modern Day Soil Mechanics, born October 2, 1883.

Since this historic day in geotechnical engineering history falls on a Saturday this year, I offer a cheer for those of us into college football (I mean, really, who isn’t this time of year, at least in the U.S.):

Two bits, four bits, six bits..a dollar

All for Terzaghi, stand up and holler!!!!!

On the more reflective side, each year I try to find some interesting fact or quote to write about. This year, I decided to read the preface of Soil Mechanics in Engineering Practice (Terzaghi and Peck, 1948) for inspiration, and thus will quote from there:

“Unfortunately, the research activities in soil mechanics had one undesirable psychological effect. They diverted the attention of many investigators and teachers from the manifold limitations imposed by nature on the application of mathematics to problems in earthwork engineering. As a consequence, more and more emphasis has been placed on refinements in sampling and testing and on those very few problems that can be solved with accuracy. Yet, accurate solutions can be obtained only if the soil strata are practically homogeneous and continuous in horizontal directions. Furthermore, since the investigations leading to an accurate solution involve highly specialized methods of sampling and testing, they are justified only in exceptional cases. On the overwhelming majority of jobs no more than an approximate forecast is needed, and if such a forecast cannot be made by simple means it cannot be made at all.”

While our technology has allowed us to measure, analyze, test, and compute huge volumes of data, as well as investigate the highly complex nature of soil-structure systems, we sometimes get caught up in the details of precision. We try to be much more precise than the materials we work with truly allow. This is not to say we should totally throw away our technology, forsaking numerical models, design software, or sophisticated in-situ testing and return to the days of slide rules (though I can use one!). There are many times, however, that an “approximate forecast” is just as “accurate” as a calculation computed to a precise number.

So, my friends, raise your glasses this weekend to toast Professor Terzaghi and our profession!


Update (10/1/10): One of my (Robert’s) mentors at my first job out of grad school, Luther Boudra, P.E. at MACTEC, wrote me this morning on the subject of accuracy and precision.  I asked him if I could share his comment (and he agreed) since I thought it was very insightful:

Robert, Professors Terzaghi’s comments remind me of something I read recently in a book about precision shooting, particularly at long range.  The author, who incidentally is both an engineer and top level shooter, was noting the difference between “precision” and “accuracy”.  Precision is exemplified by being able to repeat something to close tolerance, as exemplified in the shooting community by benchrest shooters, who are primarily interested in shooting small groups of typically 5 to 10 shots.  Hitting near the center of the target, whatever it is, is of secondary importance.  Accuracy, on the other hand, requires the ability to hit what you are aiming at, precisely.  In other words to take this to our field of endeavor, it’s possible to be “precisely inaccurate”, which the various software packages available to calculate almost anything enhance the possibility of.

Speaking of slide rules, their greatest attribute is that you have to be able to estimate the answer, rather than just writing down what shows up on the display screen.