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 November 17th, 2011
DFI held its 36th Annual Meeting October 18-21 in Boston, including the annual awards banquet. Dan was honored with the 2011 Distinguished Service Award at the banquet. The Christopher S. Bond Bridge in Kansas City, MO was honored with a Special Recognition award (one of 5 runners-up for the Outstanding Project Award). Photos of DBA folks at the event are posted below. All of the photos from the meeting can be found at this link.
Dan gave a presentation on the Alternate Technical Concept (ATC) that DBA supported for the I-70 Bridge over the Mississippi River in St. Louis, MO. The link to the presentation is below. (Some previous posts here and here and here; posts with links to other presentations here).
PowerPoint Presentation – Alternate Technical Concept: Foundations for the New Mississippi River Bridge, St. Louis – Dan Brown, Ph.D., P.E – DFI 36th Annual Conference, Boston, MA, October 20, 2011.
Dan receiving the 2011 DFI Distinguished Service Award
Robert receiving the Special Recognition Award for the Christopher S. Bond Bridge Project
Paul and Erik at the reception before the awards banquet
By David Graham, on November 9th, 2011
As massive concrete piers rise from the Mississippi river in southeast Minnesota, people have begun to take notice of what will become the longest free-standing tied-arch bridge in North America. A unique project in several respects, the new Hasting bridge has recently been featured in articles on the websites of ENR and Roads & Bridges. The ENR article is a republication of an article that originally appeared in the Minneapolis Star Tribune highlighting the construction process of the last year, with particular focus on the process of constructing the river piers. The Roads & Bridges article is a more technically in-depth piece written by the lead bridge engineer Vincent T. Gastoni, P.E., of Parsons Transportation Group. Both articles discuss some of the many geotechnical changes faced on this project. This excerpt from Roads & Bridges is a concise description of the pier foundations and some of the reasoning behind their selection:
The main river piers are concrete delta-style frames with the tied-arch superstructure fully framed into the pier through the knuckle connection. The stiffness of the foundation system was then integral to the overall force effects in the structure. The north pier is located in 190 ft of soft soils overlaying rock and supported on unfilled 42-in. driven steel pipe piles. Drilled shafts were investigated early but were not cost-effective, impacted the schedule and presented a risk to the existing bridge due to potential caving effects. Statnamic pile load testing was used to validate the vertical capacity and lateral performance of the 42-in. piles. The south pier footing is close to the rock surface; however, the rock was deeper, more sloped than expected, and the originally planned spread footing was changed to short drilled shafts during the final design. Dan Brown & Associates provided the team with geotechnical analysis and recommendations.
Our Tim Siegel pointed out that the statement “It’s a marvel of engineering that requires ingenious construction techniques, most of which are invisible to the drivers whizzing by overhead,” from the Star Tribune, is an accurate description of how our work as foundation designers and constructors is often viewed. Although much of the ingenuity and innovation that goes into the geotechnical aspects of projects often goes unnoticed by the general public, it is certainly refreshing to see articles like these. For us at DBA, it is even more refreshing to see our efforts credited by name as they were in the article by Vince when he wrote, “Dan Brown & Associates provided the team with geotechnical analysis and recommendations.”
For a design-build project with so many different geotechnical components (driven piles, drilled shafts, spread footings, retaining walls, a column-supported embankment, and light weight fill), it is hard to believe that our role as the lead geotechnical engineer is nearing completion just a little over a year after construction began. At this point, the only foundations that have yet to be constructed are some of the rock bearing spread footings at the south approach. DBA will also monitor instrumentation installed in the column-supported embankment for the next two years.
Previous blog posts by Aaron and David can be found here:Hastings Bridge Update and Hastings Update and Photo Album. Additional information can be found on the DBA project page here.
By Robert Thompson, on November 2nd, 2011
Dan and Steve co-authored an article in the Fall 2011 issue of Deep Foundations (from DFI) that covered the foundations for the recently completed record-setting Audubon Bridge in Louisiana. Dan and Steve cover not only the shaft testing, design, and construction, but also the unique cofferdam used for the tower foundations. I recently highlighted an article by Sereno Brown, P.E. of Flatiron that covered the design and installation of the cofferdam in detail.
You can receive Deep Foundations every quarter (soon bi-monthly!), as well as the DFI Journal, by joining DFI. Get information on joining at this link – click on “Membership” at the top banner.
By Robert Thompson, on October 11th, 2011
During a recent trip to Taiwan, Steve had the opportunity to participate in a lecture on base grouted drilled shaft foundations. He was invited to speak at a meeting of the Chinese Taipei Geotechnical Society (CTGS), also known as the Taiwan Geotechnical Society (TGS), by Dr. Prof. San-Shyan, Lin, National Taiwan Ocean University (current president of TGS). The meeting was held at the National Taiwan University of Science and Technology.
His visit on 21 June 2011 was noted in the August 2011 issue (Volume 5, No. 4, p82) of the ISSMGE Bulletin. During his lecture, Steve talked about the experiences of DBA with base grouting drilled shafts at the Audubon Bridge and the Huey P. Long Bridge on the Mississippi River in Louisiana. Steve said that base grouting has become a very common technology in Taiwan for high rise structures supported on drilled shafts.
The meeting is noted here on the TGS site.
(Source: ISSMGE Bulletin Volume 5, No. 4, p82)
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 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 David Graham, on April 1st, 2011
Well, I, David, have survived my first (and hopefully last) winter in Minnesota. I spent most of January and February observing the installation of the Pier 5 drilled shafts at the new Hastings bridge project in Hastings, Minnesota. In addition to the drilled shafts, there has been a lot activity at Hastings since Aaron last blogged about this project in January. A link to his post is here. All of the ground improvement piles for the column-supported embankment have been installed and approximately 75% of the caps have been poured. The 42-inch piles and pile caps for Piers 8, 9, and 10 are also complete. Piles for the north embankment retaining wall have been installed and construction of the wall has begun. Excavation for the rock bearing spread footings that will support the south land piers is in progress. Work at Piers 6 and 7 and on the north shore are currently on hold as the Mississippi River is experiencing its annual spring flood. The water level is about 14 feet above normal elevation.
I have taken the pictures Paul and I have collected over the last few months and uploaded some of the more interesting ones to a Picasa web album. The pictures are generally in chronological order and cover most of the construction process from November of 2010 right up to the end of March 2011. A link to our our video of a Statnamic load test at Hastings that Aaron blogged about is here.
By Robert Thompson, on March 24th, 2011
Paul gave a presentation recently at the Iowa ASCE Geotechnical Conference where he discussed two project case histories for LRFD design of bridge foundations. The meeting was held March 3, 2011 in Ames, Iowa. In his presentation, Paul gave an overview of the LRFD design procedure as it applies to foundations, reminding them that LRFD is not difficult and that it provides a logical framework for incorporating reliability into foundation design. Paul talked about our experiences using LRFD for foundation design for two bridges over the Mississippi River: the Hastings Bridge in Hasting Minnesota and the new I-70 bridge in St. Louis, Missouri. Both bridges are currently under construction.
A PDF of his presentation can be found at the link through the image below, or on our Presentations page.
Previous Hastings posts
Previous I-70 posts
By Robert Thompson, on February 1st, 2011
 On December 29, 2010, Audubon Bridge Constructors recently “closed” the main span of the John James Audubon Bridge between New Roads and St. Francisville, Louisiana. Watch the video featured at the top of the page at the bridge link to hear about the bridge, including the drilled shaft foundations! For something really fascinating, go to the webcams here and scroll back through the various dates. They have archived images all the way back to start of construction.
Photo: Chris Usery, Figg Bridge Inspectors
The last cables were installed on January 3, 2011 as noted on the project website:
The last two cable stays of the longest cable-stayed bridge in the Western Hemisphere were installed on January 3, 2011, five days after the spans were connected. The John James Audubon Bridge, Louisiana’s newest crossing over the Mississippi River, now has all of its 136 cable stays in place.
This bridge will be the longest cable-stayed bridge in North America when it opens later in 2011. Again, from the project web site:
The spans of the longest cable-stayed bridge in the Western Hemisphere were connected on December 29, 2010, stretching 1/3 of a mile over the Mississippi River. The John James Audubon Bridge, connecting Pointe Coupee and West Feliciana parishes in Louisiana, is approximately 92% complete. Construction of the spans began from both sides of the 500-foot tall towers earlier this year. Both sides continue to progress at a rapid pace, and now the meeting of the spans has occurred.
Steve Dapp and I had the pleasure of working with many great people during our time on site (much more time for Steve than for me!) during foundation construction. One of them, Chris Ursery of Figg Bridge Inspectors, has been great about providing us with photos now and then to keep us updated of some of the details of the bridge construction. Chris has granted us permission to share a few of his recent photos, which are shown below or can be seen in our web albums here.
Previous post on Audubon Bridge.
By Robert Thompson, on January 19th, 2011
(Image source: LakeExpo.com)
DBA is part of a team led by Parsons Transportation Group that was selected to design the replacement of the Hurricane Deck Bridge over The Lake of the Ozarks in Camden County Missouri. MoDOT has awarded the design contract to Parsons. DBA will be the lead geotechnical engineer with Terracon on the team providing drilling and laboratory services, as well as some foundation engineering support services. Parsons was chosen due to the innovative approach the team proposed that includes reusing the existing piers (from ENR.com):
MoDOT chose Parsons for proposing an innovative approach to construction that involves the use of temporary pier widening and shifting the existing superstructure over. This method will allow traffic to be maintained on the existing bridge while the new bridge is constructed, potentially resulting in significant cost savings.
A little history of the bridge can be found at Go2Lakeofthe Ozarks.com, including how it got its name:
Hurricane Deck Bridge of Ozarks crosses the main channel of the lake of approximately mile marker 35. It carries Missouri highway 5 between Versailles and Camdenton. It was built in 1936 –five years after the lake filled. It was named as Hurricane Deck because it was heard that a tornado struck that area which was locally "Hurricanes". It is a nautical term associated with river steamboats. The Hurricane Deck was the uppermost deck which provides and allows everyone to experience the pleasant breezy place and the passing scenery.
Other news links:
Lake News Online – 12/2/2010
Lake Expo.com – 12/2/2010
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