We have added Mike Holloway’s presentation at DFI SuperPile 2012 on May 17, 2012 to our Presentations Page. Mike discussed some of the issues related to pile testing and what can influence the blow counts that are often relied upon to accept piles. He covered the types of testing, limitations of various methods, and issues to consider when applying test results to production piling.
Massive prestressed concrete girders, some of them setting a record for the longest concrete girders used on a Minnesota bridge, have been set at the New Hastings Bridge, currently under construction in Hastings, Minnesota. The largest girders are 174 feet long, 8 feet tall, and weigh 108 tons! There is a video of one of these huge beams being delivered on a 16 axle truck, below. An article from the December 2011 issue of Concrete Products magazine about the girders can be found here. To date, all of the girders between the north abutment and main span have been placed. Crews are preparing piers 5 and 6 for the main span steel arches, which are scheduled to be floated in by barge and lifted into place late this year. MnDOT has two web cams where the bridge construction and the arch construction can be viewed. The Minneapolis Star Tribune has also been following the construction. Their latest article, which hails the bridge as “a monumental marvel,” can be found here.
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.
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.
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.
(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:
Good morning DBA fans! I’m here to give you the latest news on the Hastings Bridge project.
The weather has been a bit chilly in Hastings, MN but that isn’t stopping progress. Paul provided the update below and this picture of one of the beautiful mornings on the site.
Installation of the 12.75” diameter open-ended pipe piles for the column-supported embankment (CSE) is well under way. Each pile is around 165’ in length and will support a geogrid-reinforced load transfer platform (LTP). Light weight fill, or geofoam, will be used to transition from the CSE into the existing embankment.
Installation of the North Embankment retaining wall piles has begun and is about 50% complete.
The Pier 10 test pile was installed and tested with AFT’s 30MN axial Statnamic device. The pile is a 42” open-ended pipe pile with 7/8” wall and is embedded about 190’. Check out the video below. The Pier 6 test pile has also been installed and tested axially and laterally with a Statnamic device.
That’s all for now, but come back later for additional updates on this exciting project. Thanks for reading!
The kcICON project in Kansas City has been completed six months ahead of schedule and within budget with all lanes and ramps being open on December 18th. Demolition has begun on the existing Paseo bridge. You can see some photos of the demolition (like the one in this post – thanks kcICON!) at their Facebook page. It was a great experience for us to have been a part of this project. If you want to see all of our previous posts on this, click here. Other points of interest are linked below.
Dan recently played the part of storyteller at the Southeastern Transportation Geotechnical Engineering Conference (STGEC) 2010 conference in Charleston, West Virginia when he gave the lunch presentation on the conference’s first day. He took the audience on a trip down the Mississippi River from a foundation engineer’s perspective, talking about several bridges that DBA has had the pleasure to work on, or is still working on, along the river the last few years. Dan began with the I-35W Bridge replacement in Minneapolis, Minnesota and ended at the Huey P. Long Bridge in New Orleans, Louisiana. Stops along the way included the Hastings Bridge (Hastings Minnesota), the new I-70 Bridge (St. Louis, Missouri), and the Audubon Bridge (New Roads/St. Francisville, Louisiana). Dan covered some of the technical issues/problems associated with each project and the solutions applied to complete the foundations (or complete the design). It was a very informative talk presented in a unique way that everyone at the luncheon seemed to enjoy. Dan’s presentation is now available on our Presentations Page.
Immediately after lunch, Robert made a presentation that described some of the pile load tests performed on two of the storm protection projects in New Orleans that DBA was privileged to be involved with through Kiewit. By following Dan, it provided a little continuity to the story as Robert took the group below the Huey P. Long Bridge to the levees and canals downstream of New Orleans. Robert’s presentation can also be found on our Presentations Page.
The Lunda/Ames design-build joint venture (Lunda Construction Company of Black River Falls, Wisconsin and Ames Construction, Inc. of Burnsville, Minnesota) has been awarded a contract to build the new Highway 61 Hastings Bridge over the Mississippi River in Hastings, Minnesota. Parsons Transportation Group is the designer and DBA is performing geotechnical design of the bridge foundations and settlement mitigation as a sub-consultant to PTG.
Here is the existing bridge that is being replaced (viewing from upstream):
In addition to several relatively large approach spans, the new bridge will include a 545ft long free-standing arch main span with four lanes of traffic and a 12 foot wide common use pedestrian/bike path. The new bridge will allow additional parking and an artistic plaza area south of the river. An anti-icing system will be installed to help achieve the 100-year design life.
On the south side of the Mississippi River, the bridge foundations will consist of spread footings bearing on dolostone bedrock. The remaining bridge foundations will utilize 42in diameter pipe piles. Several Statnamic load tests, both axial and lateral, will be performed by our friends at AFT.
Settlement mitigation is required beneath the North Embankment due to several relatively thick and deep strata of compressible fine-grained soils. The embankment will also be heavily instrumented to evaluate performance of the embankment and mitigation technique.
Preliminary work including subsurface investigation has begun. The subsurface investigation is being performed by Braun Intertec under sub-contract to DBA. Test piles will be installed in early September, 2010 with subsequent load testing soon after.
The awarded design-build contract is for $120M. The estimated project completion date is May 13, 2013.
Here is a sampling of the local news on the project award:
Hastings Star-Gazette: Many articles, ongoing
9/22 Star Tribune: New Hastings Bridge is on the way
July 1 South Washington County Bulletin: Bridge design chosen: It will be the tied-arch
July 1 Minneapolis/St. Paul Business Journal: Lunda/Ames team wins $120M Hastings Bridge contract