Get the New FHWA Drilled Shaft Manual
Get the NCHRP Synthesis 418 – Pile Criteria From Test Pile Data
Dan’s Speaking Schedule March 16, 2012 - "Advanced" Design and Construction Issues with Drilled Shaft Foundations; Case Histories - ADSC Equipment EXPO and Technical Conference - San Antonio, Texas
March 26-28, 2012 - State of the Art and Practice for Drilled Foundations - GeoCongress 2012 - ASCE/Geo-Institute - San Francisco, California
Other DBA Team Speaking Appearences Tim Siegel (January 22, 2012): Innovative Techniques for Characterizing Karst Terrain, Workshop on Geo-innovation in Subsurface Exploration, TRB Annual Meeting, Washington, D.C.
John Turner and Robert Thompson (February 21-23, 2012): NHI Drilled Shaft Course - Kansas DOT, Topeka, Kansas
Robert Thompson (February 24, 2012): Conservatism in Drilled Shaft Design When
Utilizing Rock Sockets, Alabama Transportation Conference, Montgomery, Alabama
Tim Siegel (March 15, 2012): Micropile Design Installation and Performance for the Foothills Parkway, ADSC Equipment EXPO and Technical Conference, San Antonio, Texas
Robert Thompson (March 15, 2012): Full-Scale Load Tests on Drilled Shafts in Tennessee and Georgia, ADSC Equipment EXPO and Technical Conference, San Antonio, Texas
Erik Loehr (March 15, 2012): Slope Stabilization Using Micropiles, ADSC Equipment EXPO and Technical Conference, San Antonio, Texas
TBA (April 10-12, 2012): NHI Drilled Shaft Course - South Carolina DOT, Columbia, South Carolina
Conferences, Meetings, Seminars, Workshops
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By Robert Thompson, on September 26th, 2011
 It seems that social media and on-line communications have become a major part of our day-to-day communications. If you are like me (Robert), I find it rather annoying at times to filter through what you get to find what you really want or need. Now there is an on-line social networking/community for the geoengineering field – GeoWorld. This new “spot on the web” is a collaboration of Geoengineer.org and ISSMGE (International Society for Soil Mechanics and Geotechnical Engineering).
After more than two years of development, Geoengineer.org, in collaboration with the ISSMGE, is pleased to announce the development of Geoworld!
Geoworld is a new, free, professional networking platform for professionals, companies and professional organizations in the geoengineering profession. It promotes professional networking, collaborations and information dissemination at a global scale.
Geoworld revolutionizes the way information is circulated and even generated in the geoengineering field. It will serve as a platform to promote professional interactions, foster the formation of formal and informal groups, and support innovation in the geoengineering field at a global scale.
Geoworld is very easy to use and powerful, and has features that are specifically suited for geotechnical engineering professionals. Hundreds of geotechnical engineers as well as companies and organizations have already joined since the first announcement of Geoworld last week.
Here is a video link introducing Geoworld.
Look for DBA and ask to become a Contact. Also look for me and other DBA folks. See you there!
By Robert Thompson, on September 14th, 2011
 The Transportation Research Board of the National Academies has published a National Cooperative Highway Research Program synthesis report by Dan and Robert: NCHRP Synthesis 418–Developing Production Pile Driving Criteria From Test Pile Data. This synthesis provides a survey of the current practices used by transportation agencies to develop pile driving criteria, with special attention on the use of test pile data. The report covers issues related to developing driving criteria, the current practices used by the responding agencies, recommended useful practices that were identified, along with descriptions of the practical approach several agencies use to integrate a range of technologies to develop pile driving criteria under typical conditions. The information collected indicates that practices used by transportation agencies to develop pile driving criteria for production pile installation can be described as highly variable in terms of the level and sophistication of the testing performed.
Included in the report are:
- Responses from a survey sent to all 50 state departments of transportation plus the District of Columbia and Puerto Rico (44 of the 52 agencies provided responses).
- Interviews performed by telephone or in-person of nine of the responding agencies selected based on the written survey responses.
- A comprehensive literature review on the range of practices included in test pile programs and their use in developing production pile driving criteria.
- Discussions of the survey results.
- Useful practices identified from the surveys.
- Identification of research needs for this topic.
To purchase the print version of this report or get a PDF, follow this link to TRB. Click the “View This PDF” to get the PDF.
Please note that if you order the printed version, Appendices B and C (copies of the completed survey forms and interview notes) are available via download only.
By Robert Thompson, on August 31st, 2011
Dan will be honored at the DFI 36th Annual Conference on Deep Foundations in Boston, October 19 to 21. He will receive the award at the annual awards banquet on Thursday, October 20th. From DFI:
The Deep Foundations Institute is pleased to announce Dan Brown, P.E., Ph.D., as the recipient of the DFI 2011 Distinguished Service Award. The award, in its 31st year, honors individuals chosen by their peers for exceptional contributions to DFI and to the industry.
Brown began his career with a B.S. from Georgia Tech, and later received his Ph.D. at the University of Texas, Austin, in only 28 months, while working. He then taught at Auburn University for 22 years before setting up his own consulting firm in Tennessee. The Winter 2011 issue of the DFI magazine included a profile of Brown that chronicled the universal admiration and regard for him within the industry. He was cited by others for his expertise, his intelligence and ability to teach others. Brown and his firm are sought out for advice everywhere.
Follow this link to see the full press release. We’ll post pictures after the ceremony.
By Robert Thompson, on August 25th, 2011
 Tim has authored a Technical Note in the most recent issue (June 2011) of the DFI Journal. The note is entitled “Simplified Settlement Model for a Shallow Foundation on Composite Ground with Rigid Piles”. From the Abstract:
A piled raft refers to a shallow foundation that is structurally connected to the piles, while composite ground refers to a soil-pile matrix where the piles are not structurally connected. The design objectives for both a piled raft and composite ground are (excluding special considerations such as expansive soil): (1) to provide a sufficient ultimate resistance and (2) to distribute the load into the soil-pile matrix so that the settlement experienced by the shallow foundation is within tolerable limits. A simplified model is proposed for a shallow foundation on composite ground where the foundation settlement is estimated as the sum of the downward movement of the piles plus the downward movement of the shallow foundation relative to the pile head. The proposed simplified
model is applied using conventional geotechnical analyses for two hypothetical examples of shallow foundations undergoing compression settlement.
This paper was originally published in DFI’s bi-annual journal, Volume 5, No. 1 in June 2011. DFI is an international technical association of firms and individuals involved in the deep foundations and related industry. The DFI Journal is a member publication. To join DFI and receive the journal, go to www.dfi.org for further information. ”
You can also subscribe to the DFI Journal here.
By Robert Thompson, on July 31st, 2011
As noted earlier on this blog, the Audubon Bridge opened a little bit earlier than planned. Although over a year old, an article recently came to my attention that puts a spotlight on the unique engineering and construction that went into the cofferdams for the two main bridge piers in the Mississippi River. The article is “John James Audubon Bridge Project – Cofferdam Construction for the Main Span Pier Foundations”, published in the February 2010 issue of Louisiana Civil Engineer, the Journal of the Louisiana Section of the American Society of Civil Engineers.
The article’s lead author, Sereno Brown, P.E., was the construction team’s Project Engineer for the design-build project. In the article, Mr. Brown outlines the issues that led to the team selecting a pre-cast concrete cofferdam over other methods, the design methodology, and then the construction of the cofferdam. The effort posed several significant design and construction challenges, including the sequence of lowering the cofferdam into place through a set of hydraulic jacks. The entire process was truly an amazing engineering and construction feat.
Download the article here.
By Robert Thompson, on July 26th, 2011
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.
By David Graham, on July 22nd, 2011
Constructability Considerations When Designing Drilled Shaft Foundations for Bridges
The May/June 2011 issue of ASCE’s Geo-Strata focuses on bridge geotechnics. Dan contributed an article to this issue summarizing key constructability considerations for bridge drilled shaft designers. Specifically, the article focuses on fresh concrete properties and reinforcement design. Discussion of self consolidating concrete (SCC) and column-shaft connections is also included. The article has been added to our publications page and is available through the link above. Additional details related to bridge drilled shaft constructability can be found in the 2010 FHWA Drilled Shaft Manual here.
By Robert Thompson, on July 20th, 2011
The John James Audubon Bridge was opened to traffic on May 10, 2011 a little earlier than planned. While the project is not 100% complete, the bridge was sufficiently complete to allow an emergency opening due to closure of the nearby ferry the bridge is replacing. From the project website:
Due to the high level of the Mississippi River causing the closure of the New Roads/St. Francisville ferry, the Louisiana Department of Transportation and Development (DOTD) opened the John James Audubon Bridge at 10 a.m. on Thursday, May 5, 2011. This emergency opening allowed continuous river-crossing access for traffic affected by the ferry closure. The ferry, which carried approximately 720 vehicles per day according to 2009-2010 DOTD statistics, is permanently closed with the opening of the Audubon Bridge.
Construction is still ongoing and could affect traffic until the project is 100% complete later this year.
By Robert Thompson, on June 27th, 2011
The planned second load test in the ADSC research project for rock sockets in the Southeastern U.S. is moving closer to execution. Bruce Long of Long Foundation Drilling Company provides this update:
To Fellow Load Testers,
We want to thank everyone who submitted questions or comments regarding the preliminary load test program submitted to us by Dr. Dan Brown. Those comments, and more, will be considered while fine-tuning the program.
Because we have several companies donating their time and money, we have to be flexible with respect to the installation and testing dates. We have tentatively selected some dates, but these are subject to change depending upon the workloads of those volunteering their efforts. We hope to begin shaft installation during the last two weeks of July (weeks beginning the 18th or 25th). The actual load testing would probably take place the week of August 8th, with the actual test date being decided upon by sometime in early July (I hope to give everyone at least a 3-4 week notice).
The actual test date would include a field day visit by all interested parties to the test site at Foundation Technologies office in Lawrenceville, GA. Activities will include a load testing discussion led by Dr. Dan Brown, along with lunch. We would then move to the test site where Loadtest, Inc. will be conducting the Osterberg Load Test on our first shaft. A discussion of the testing process and procedures by Loadtest will precede the actual testing (We will be submitting information later regarding a load test contest where each of you will get to predict the outcome of the test with a special prize going to the winner). We also hope to be drilling on the second shaft that day and will be discussing the drill rigs, tools, and other equipment being used, as well as having the other Osterberg cell available for viewing. This site visit proved to be very well received when we did it in Nashville at the last load test. We hope for a big turnout that day.
I wanted to give everybody a brief update and will be in touch when additional information becomes available in the near future. Thank you for your interest, and if anyone has any questions regarding this plan, please feel free to call me at your convenience.
Bruce Long
President
Long Foundation Drilling Co.
Previous post is here.
The test site page is here.
The main page for the research project is here.
By David Graham, on June 14th, 2011
We are pleased to announce that John P. Turner, Ph.D., P.E., has joined our firm as a Senior Principal. Turner is Professor Emeritus, University of Wyoming, where he spent the past 25 years teaching and conducting research in geotechnical engineering. He has undergraduate degrees in both Geology and Civil Engineering and earned his doctorate in Geotechnical Engineering from Cornell University. John will bring his considerable expertise in design and construction of deep foundations to our practice. He is a co-author of the 2010 FHWA manual “Drilled Shafts: Construction Procedures and LRFD Design Methods” and the author of NCHRP Synthesis 360, “Rock-Socketed Shafts for Highway Structure Foundations”, as well as over 100 technical publications on the topics of deep foundations, earth retention, and landslide stabilization. Early in his career John was an engineering geologist with Herbert and Associates and he maintained his involvement in consulting throughout his academic career. Recent projects include design of rock-socketed drilled shafts for bridges at Pitkins Curve in Big Sur and the Antlers Bridge on I-5 in northern California. John is a recipient of the President’s Award and the Distinguished Service Award from the ADSC: International Association of Foundation Drilling. He has maintained active membership in ASCE for over 30 years and is a past chairman of the Committee on Deep Foundations of the Geo-Institute of ASCE.
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