Tag Archives: O-cell

Dan Brown Selected for 2012 DFI Osterberg Lecture

Dan has been selected by the DFI Educational Trust to deliver the 4th Annual Osterberg Memorial Lecture.  The lecture is given at a benefit dinner for the  DFI Educational Trust Scholarship Funds.  The dinner this year will be held in conjunction with the joint DFI-ADSC Seminar Drilled Shafts: Top to Bottom on September 12th in Denver.  From DFI:

The Osterberg Memorial Lecture has been established in honor of Dr. Jorj Osterberg, inventor of the Osterberg Cell, to recognize innovations in the deep foundations construction industry and related to deep foundations engineering design, testing or education; all aspects of his lifelong contributions.

According to the invitation letter from DFI, the committee selects a “person who encompasses the spirit of the lecture which is to emphasize innovations or contributions to the deep foundation industry and related to deep foundation engineering design, testing or education, all aspects of Jorj Osterberg’s lifelong contributions.”

Previous lecturers are:

2011: John. H. Schmertmann, Ph.D., P.E.

2010: Bengt H. Fellenius, Dr. Tech., P.Eng.

2009: Clyde Baker, Jr., P.E., S.E., and Robert G. Lukas, P.E.

About the DFI Educational Trust:

Today DFI Educational Trust is an independent charitable foundation of the Deep Foundations Institute. The TRUST manages the Annual Student Paper Competition, the Annual Young Professors Paper Competition, the History of Deep Foundations Poster Program, the Sustaining Membership Fund and the Paul DeBruyn Memorial Student Scholarship Fund, the Berkel & Company Contractors Inc. Scholarship Fund, and the Annual Osterberg Memorial Lecture. These programs, along with future initiatives, will play a large role in enabling better Industry-Academia communications by instilling an interest in the heavy construction and civil engineering sciences in both high school and college level students.

Currently the TRUST plans to awards annually four Student Scholarships in the amount of $12,500 each to undergraduates studying in the field of civil, geotechnical or construction engineering. Auburn University, Carnegie Mellon, University of California-Berkeley and University of Illinois are awarded the funds and select students based on the TRUST’s criteria of majoring in one of the above fields of engineering with interest in deep foundations construction and having financial need. Additionally the TRUST provides scholarships to high school students in partnership with the ACE Mentor Program for those interested in pursuing college studies in engineering or construction management. These scholarships are endowed through charitable donations and fund raising events, such as golf outings and benefit dinners.

Creating opportunities for students to see Industry in action is another large element of the DFI Trust mission, by providing affordable student attendance of DFI Conferences and technical seminars, site visits and live demonstrations or by bringing Industry Experts into the classrooms. The TRUST is proud to announce the formation of its first student chapter at UC-Berkeley in 2009.

ADSC Lawrenceville Test Site–Prediction Contest!

Update (7/31/11)Field Day set for Thursday, August 18th – More info here!

Back by popular demand, we will hold a prediction contest for the second test site in the ADSC drilled shaft research project for rock sockets in the Southeastern U.S.  Contestants are encouraged to download the information linked below and then submit their predictions of unit side resistance and base resistance that will be measured by the O-cell tests.  The winner will be announced at the field test and demonstration day on site, as well as published in this blog along with all submitted predictions.

Two test shafts will be installed July 26 – 29th at the yard of Foundation Technologies, Inc. One will include a rock socket to attempt to test side and base resistance in the rock socket.  The other shaft will be drilled to “rock auger refusal” to attempt to test side resistance in the partially weathered rock (locally termed PWR) and base resistance at “rock auger refusal”.  In the Piedmont area, the highly weathered upper rock zone is commonly called PWR.  Another common usage is “rock auger refusal” to define where “hard rock” begins.  It is thought that designers may be overly conservative with base resistance values at “rock auger refusal”.  Hopefully this test will provide useful data in that regard.

Testing will occur during a field demonstration day in mid-August. We’ll post the date once it is finalized.

Information to include the test shaft configurations and exploratory boring data can be downloaded here.

The contest entry form along with instructions for submission can be downloaded here.

We will have Aaron on site to observe and take lots of pictures.  We’ll post his photos of the excavations as soon as we can (check the project web page soon after August 1st) to assist in making predictions.

All predictions must be submitted by the close of business, August 12, 2011.

For more information, visit the test site page.

Previous posts.

New I-70 Bridge Featured in Foundation Drilling Magazine

The new I-70 bridge over the Mississippi River near St. Louis, Missouri is quite the project.  When completed, it will be the third longest cable-stayed bridge in the United States, with a 1,500-ft main span.  Most significantly for the geotechnical community, the bridge made history when one of its 11-ft diameter drilled shafts resisted a world record breaking 36,000 tons (bi-directional) during an O-cell load test.  The bridge has already seen press in Civil Engineering Magazine (July 2010, page 30-32), at ENR.com, and in a post by Robert on this blog.  Now, an article by DBA’s Paul Axtell is featured in the September/October issue of Foundation Drilling Magazine.  The editor summarized the article saying:

The information in the following article is a composite of material that came to Foundation Drilling Magazine from three separate sources.  Part I is based on information gleaned from an article that was published on the Associated Press news wire.  Part II is excerpted from ENR’s August 18th, E-Newsletter.  Part III was provided by Paul Axtell and Dan Brown of ADSC Technical Affiliate company, Dan Brown and Associates.  The bridge project is of interest in general.  The Osterberg Load Cell test will be of particular interest to professionals in the deep foundation industry, and specifically for those who work in the drilled shaft segment.

Axtell, P.J. (2010). “Mississippi River Bridge Project Includes Record Load Test: A Three Part Story”, Foundation Drilling, Vol. 31, No. 7 September/October 2010.

World Record O-Cell Load Test in St. Louis, MO!

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DBA was part of foundation engineering and construction history while participating in a drilled shaft load test for the New I-70 Mississippi River Bridge in St. Louis, Missouri.  A new O-cell world record of 36,000 tons (bi-directional) was achieved on the test, besting the former record of just under 32,000 tons set in 2005 in Korea (see here).

The test shaft was built by MTA (a joint venture of Massman/Traylor Brothers/Alberici Constructors) as part of an Alternative Technical Concept (ATC) that MTA submitted in their winning bid.   During the bid phase, the owner allowed ATC’s to be submitted by pre-qualified teams.  These ATC’s were unique to the team that submitted them (e.g., each team was allowed to submit their own ATC’s if they desired, but the ATC’s were not shared amongst all the teams).  DBA worked with MTA to develop an ATC that optimized the drilled shaft foundations shown in the “baseline” drawings provided by the owner.  That ATC provided a more economical foundation solution that was accepted, bid, and awarded (note MTA also had the option of bidding the “baseline” drawings as-is).  A full-scale load test on a dedicated test shaft using the Osterberg Cell (O-cell) test method was included in the ATC to: 1) prove the design values used for the resistance in the rock socket; and (2) take advantage of higher resistance factors for using a load tests as opposed to only calculations.  The baseline drawings did not include a load test.

Loadtest, Inc. performed the load test.  The bottom-up static load test applied slightly greater than 36,000 tons (bi-directional) to the shaft resulting in about 1/8in of upward movement of the shaft and about the same magnitude of downward displacement at the base.  The rock socket was about 23ft deep and 11ft in diameter in very hard limestone.  Four 34in O-cells placed at the base of the shaft were loaded to 150% of their rated capacity to achieve the record load.

UPDATE (8/4/10): The bridge was featured in the July 2010 issue of Civil Engineering magazine from ASCE in the “News” section.  Follow the link below and then go to Page 30.

Civil Engineering July 2010

UPDATE (8/17/10): Press Release from MTA (contractor joint venture).

UPDATE (8/18/10): ENR.com Article

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