All posts by Robert Thompson

US 231 Emergency Slide Repair – Laceys Spring, Alabama

DBA has the great fortune to be working with the Alabama Department of Transportation (ALDOT) on a very interesting bridge project in Lacey’s Spring, Alabama just south of Huntsville, Alabama.  On February 12 and 13, 2020 a large landslide occurred on SR-53 (US-231) at milepost 301.7 in Morgan County approximately 1.7 miles south of the Laceys Spring Community.  The slide completely severed the 4-lane divided highway which is a major commuting route between Huntsville and several communities south of the city.  Many of the workers at the U.S. Army Redstone Arsenal, NASA Marshall Space Flight Center, and the contractors and vendors that support these two major installations live in the communities impacted by the closure of the highway.  Detours were established on existing state and county roads, but these added 30 to 60 minutes to commute times, depending on time of day.  ALDOT was under significant pressure from the impacted communities to quickly solve the problem and reopen the road.

ALDOT drill rigs performing exploratory drilling (DBA)

 

ALDOT drilling crews were immediately mobilized to the site to begin drilling exploratory borings and install slope inclinometer casings for monitoring slide movements.  The Department of Civil Engineering at Auburn University was engaged to perform geophysical testing in conjunction with an existing research project for ALDOT.  Geotechnical engineering firm TTL also assisted with field investigation efforts. 

DBA and ALDOT immediately began evaluating several alternate concepts for stabilizing the slide and reopening the road during the soil and rock exploratory drilling.  The design team looked at several retaining wall options, a complete rebuild of the roadway, and bridges.  ALDOT selected a solution that removed most of the existing roadway embankments (built in 1947 and 1970) to reduce loading on the slope and then spanning the slide area with bridges built on the existing road alignments, with the bridges designed to withstand future movements of the slope.  

The bridges are two-lane structures, one Northbound and one Southbound, each about 947 ft in length.  The superstructure is AASHTO BT-72 concrete girders and a concrete deck.  There are seven spans in each bridge each about 135ft long.  The grading work was begun while the bridge was still being designed to accelerate the schedule and shorten the time the road would be closed.

The foundations for each pier are a pair of 9.5ft diameter, permanently cased drilled shafts with 9ft diameter rock sockets.  The sockets are 14ft long into the limestone and shale bedrock.  The limestone uniaxial compressive strengths range from 10,820 psi to 28,100 psi. 

After much design and analysis in a highly compressed schedule, a bridge contract was let for bid in early May 2020, less than 3 months after the slide occurred.  Brasfield & Gorrie was the successful bidder and awarded a $15 million contract that has incentives for finishing early, and disincentives for finishing late. 

 

ALDOT UAV flight June 16, 2020

ALDOT UAV flight July 07, 2020

ALDOT UAV flight July 23, 2020

ALDOT UAV flight July 28, 2020

ALDOT UAV Flight Aug 08, 2020

 

Excavating first shaft on the site (DBA)

 

A.H. Beck (Beck) is the drilled shaft contractor, drilling each shaft, placing reinforcement, and placing concrete.   The permanent casing is 5/8 inch wall thickness spiral weld 60ksi steel. The shafts are reinforced with a 1.5inch wall thickness, 8ft diameter, 60ksi steel pipe. These pipes are rolled and welded.

8ft diameter x 1.5in wall steel pipe for shaft reinforcement (DBA)

 

Inner structural pipe (1.5in) and outer casing (5/8in) (DBA)

 

The pair of shafts for each pier is connected by a reinforced concrete grade beam 10ft wide by 7ft high by 46ft long. To connect the shafts to the grade beam, a 14ft long reinforcement cage is placed in each shaft, embedded 8ft into the shaft with 6ft embedded in the grade beam. The cage consists of 28 No.18 Grade 75 bars.

Grade beam at NB Bent 7 with column steel (DBA)

 

Completed shaft with reinforcing cage to embed in grade beam (DBA)

 

The project includes a robust instrumentation plan with ShapeArray inclinometers installed in each shaft and in the slope, supplemented by traditional inclinometers in the slope and vibrating piezometers to monitor groundwater levels.  DBA and ALDOT will monitor the bridge and slope, intending to be able to measure displacement and calculate strain and loads in the shafts should the slope move again in the future.

Foundations are scheduled to be completed by the end of July 2020.  The deadline to have the bridge open to traffic is early December, 2020, but Brasfield and Gorrie has an aggressive plan to complete the project early and earn the bonus for early completion.   Volkert is the CE&I Consultant on the project for ALDOT, providing construction management and inspection services for the project.

Click HERE for some of the photos DBA team members have taken during construction.

To see aerial views from ALDOT’s UAV flight taken on July 10, 2020, click HERE.

 

 

DBA Announces Officer Transitions

DBA is excited to announce recent transitions within the company.

Dan Brown, Ph.D., P.E., D.GE, is turning over the reigns of leadership to the next generation in the firm and stepping down as President.   While stepping back from day-to-day management of the company, Dan will remain fully involved in technical aspects and client service in the role of Chief Engineer where he will continue to focus on developing practical solutions to complex and challenging foundation issues.

Three Senior Principal Engineers will assume the roles of the officers of DBA.  Tim Siegel, P.E., G.E., D.GE  has been promoted to Chief Executive Officer.   Paul Axtell, P.E., D.GE has been promoted to Chief Operating Officer.  Robert Thompson, P.E., D.GE has been promoted to Chief Financial Officer.   Tim, Paul, and Robert will provide the management and leadership for the continued growth of DBA and for DBA to provide value to its clients and continue to be a key contributor to the practice of geotechnical engineering.

Tim Siegel, CEO Paul Axtell, COO Robert Thompson, CFO

 

DBA Grows – 2020 Edition!

DBA is happy to announce our two latest additions to the team: Dan Ding, Ph.D., P.E. and Andy Boekmann, Ph.D., P.E.  Dan joined us as a Project Engineer in October of 2019 while Andy came on board as a Senior Engineer in February of this year.   Read a little bit about both of them below.  Go to our About us page to see their resume as well as everyone else on the DBA Team.

Dan Ding, Ph.D., P.E.

Dan received her Ph.D. degree in Civil Engineering from the University of Missouri. Dan specializes in site characterization, geotechnical laboratory testing, Load and Resistance Factor Design, and reliability analysis. Before joining DBA, Dan worked as an adjunct assistant professor at the University of Missouri to teach undergraduate and graduate engineering courses as well as conduct national and state research projects. She also worked as a laboratory geotechnical engineer at Geocomp in Acton, MA for a year after graduation.  Dan is based in Columbia, Missouri.

Andy Boeckmann, Ph.D., P.E.

Prior to joining DBA, Andy was a research engineer at the University of Missouri, where he performed research on topics including post-grouted drilled shafts, reliability of geotechnical designs, foundation reuse, and geotechnical asset management. Andy also earned a Ph.D. at the University of Missouri; his dissertation examined the reliability of foundation designs based on site-specific load tests. Andy is the lead author of two NCHRP Synthesis reports, including Current Practices and Guidelines for the Reuse of Bridge Foundations. Prior to working at MU, Andy was a consulting geotechnical engineer for URS Corp. in St. Louis, where he performed design and analysis for large projects, including post-Hurricane Katrina levee design in New Orleans. Andy is an active member of the Deep Foundations Institute, including serving as the vice-chair of the Subsurface Characterization Committee.  He is also based in Columbia, Missouri.

FHWA GEC 10 Update for 2018 Released!

UPDATE!  Posting of the PDF to the FHWA Resource page has been delayed while the formatting issues noted below are worked out. 

CLICK HERE for a Final DRAFT for use until FINAL document is posted by FHWA.

The long anticipated update to FHWA GEC 10 Drilled Shafts: Construction Procedures and Design Methods has finally been released by FHWA, The same team that authored the major update in 2010 that shifted design from ASD to LRFD also completed this update: Dr. Dan Brown, P.E., D.GE, and Dr. John Turner, P.E., D.GE of DBA, Dr. Erik Loehr, P.E. of the University of Missouri and DBA, and Mr. Ray Castelli, P.E. of WSP.

This version is an update of the 2010 publication.  A complete list of changes made since 2010 is in the opening chapter.  Some of the revisions include:

  • streamlining materials covered in other GEC publications (for example, site investigation and lateral loading) to focus on aspects particular or unique to drilled shafts;
  • updates to reflect the evolution of construction procedures, tooling, materials, drilling fluids, and concrete placement;
  • updated design equations for axial loading, particularly for earthquake loading;
  • updated group design to reflect recent changes to AASHTO design guidelines;
  • updates on integrity testing (including use of Thermal Integrity Profiling, or TIP); and,
  • an outline for a process for assessment and acceptance of drilled shafts based on inspection records and integrity tests.

You can download the new PDF here.  The PDF posted is “preliminary” with some minor formatting and other items to be cleaned up by the fall.

2018 Tennessee Earthquake GEER Report

Tim Siegel was one of four co-leaders of a Geotechnical Extreme Events  Reconnaissance (GEER) team that investigated the impacts of the 2018 Tennessee Earthquake that occurred near Decatur, Tennessee on December 12, 2018.   Among the team members were Ali Leib and Mark Madget.  The team performed reconnaissance of the area around the epicenter of the quake and prepared a report of their observations.

The quake occurred at 4:14 am EST approximately 12 km north-northeast of Decatur, Tennessee, which is about 240 km southeast of Nashville, TN.  The highest recorded peak ground acceleration (PGA) was 0.0215g approximately 36 km from the epicenter.  At least 21 aftershocks were recorded through December 18, 2018.  The GEER team did not encounter any evidence of earthquake-induced damage in the areas they visited.  Organizations such as the Tennessee Valley Authority (TVA), the Oak Ridge National Laboratory (ORNL) , and the Tennessee Department of Transportation (TDOT) “reported that either there was no damage to their facilities or that their operations were unaffected due to earthquake.”

The team’s report can be downloaded from GEER here.  Click the image below to see the list of the entire team.

GEER is a “volunteer organization of geotechnical engineers, engineering geologists, and earth scientists from academia, industry, government organizations, and non-profit organizations.”  They assemble teams to conduct detailed reconnaissance after extreme events (earthquakes, landslides, floods, hurricanes, etc.) in order “to  obtain valuable perishable information that can be used to advance research and improve engineering practice.”

To find out more about GEER, visit their website.

Pre-Bid Load Testing for the Mobile River Bridge and Bayway Public Private Partnership (P3) Project

DBA has been fortunate to be involved as a consult to Alabama Department of Transportation (ALDOT) for the  Mobile River Bridge and Bayway Project.  This project represents Alabama’s largest ever investment for a single infrastructure project.  The project includes a cable stayed bridge over the Mobile River and seven miles of bridge over Mobile Bay.  Bridge foundations therefore represent a major component of the estimated $2 billion project cost.  DBA serves as a foundation consultant under subcontract to Thompson Engineering, Inc..  Thompson is one of the ALDOT Advisory Team partners, the other partners being HDR and Mott MacDonald.

With the tremendous volume of foundations required for the project, the DBA/Thompson team worked with ALDOT’s Geotechnical Division to develop a pre-bid load test program to help reduce some of the risks that would face both ALDOT and prospective concessionaires.  Performing a deep foundation load test program during the procurement phase of a Public Private Partnership (P3) project can help the prospective concessionaires better define foundation design parameters and reduce uncertainties and risks related to constructability of the foundations.  The reduced risk leads to reduced costs by allowing the concessionaire to develop a more efficient design while minimizing contingency costs and potential delays related to foundation constructability or performance.

The load test program was designed to include the most likely foundation types that the prospective teams might use.  Several types of driven piles were installed and tested, including typical square and cylinder concrete piles used on the Alabama coast plus steel H-piles and an open-ended steel pipe pile.

All driven piles were subject to dynamic testing with a Pile Driving Analyzer during driving.  Restrikes with dynamic testing were conducted on all driven piles to evaluate potential strength gain with time.  Jetting techniques were specified for some piles to evaluate this installation technique which could potentially be used during construction.

Traditional axial static load tests were performed on steel HP14x89 and 18in Precast Prestressed Concrete (PPC) square piles.  Rapid (Statnamic) axial load tests were performed on 36 in PCC square piles, 54in PCC cylinder, and 60in steel open-end pipe piles.

A 72in diameter drilled shaft foundation was also installed and tested.  Axial load testing was done using a bi-directional load cell (AFT A-Cell).  Lateral load testing was done using the Statnamic device.

 

Here are some videos of the Statnamic testing, with slow motion action!

 

Foundation contractors that are part of a concessionaire team pursuing the project were allowed to bid the load test program.  Jordan Pile Driving was the successful bidder for the $3.7 million test project.  AFT provided the testing services for the project – dynamic, static, Statnamic, and A-Cell.

A summary of the results can be found in a presentation made to ALDOT at the 62nd Annual Alabama Transportation Conference on February 13, 2019.   (Click HERE to get the presentation). Publication of the results is anticipated to be made in the DFI Journal in the future.

Dan Brown awarded A Golden Beaver

(One more catch-up on “older” news!)

In January of 2018, Dan was awarded the coveted Golden Beaver  Award in Engineering by The Beavers.  The award was given at the 63rd Annual Golden Beavers Award Dinner on January 19, 2018 in Los Angeles.

The Beavers is a social and honorary organization organized and managed by members of the heavy construction industry.

The purpose of the Beavers is to promote goodwill, friendliness and consideration within the heavy engineering construction industry; to give recognition to those men and women who have demonstrated particular skill, responsibility and integrity; and to encourage and support entry of promising young individuals into heavy engineering construction.

The Beavers hold two major events annually. The Beavers Awards Dinner is held in mid-January, where individuals are recognized with a Golden Beaver Award for their achievements and contributions to the heavy construction industry in the categories of Management, Supervision, Engineering and Service & Supply.

Dan was honored with the award for his expertise and contributions to the deep foundations industry and its impacts on the heavy construction industry.

 

DBA staff additions for 2018 (and Earlier)

It has been a busy time since our last post, so it is time to “catch up” on the growth of our staff over the last year or so since the last update. Here are the newest faces of DBA. You can find resumes on the About US – Other Engineers page.


Cody Coonradt, E.I. (Staff Engineer) He had several years of experience as a field and laboratory technician before completing his BS and MS degrees in Civil Engineering at the University at Buffalo, State University of New York. While completing his BS and MS degrees, Cody worked at a geotechnical engineering firm in Buffalo, NY. His experience includes site investigation, stormwater management, slope stabilization, load transfer platforms, retaining structures, and ground improvement. Cody and his family have moved to Knoxville, Tennessee where Cody will be based.

Tayler Day, E.I. (Project Engineer) joined us in Knoxville in October of 2016. He is a graduate of the University of Missouri, with BS and MS degrees in Civil Engineering. Talyer is in the process of completing his Ph.D. at Mizzou as well. Tayler is applying his experience in field testing to many projects with a wide variety of foundations types, working from our Knoxville office.

Isaac Jeldes, Ph.D. (Project Engineer) started at DBA in August, 2017. He is a native of Chile and is a civil engineer whose passion is geotechnical engineering. He holds MS and Ph.D. degrees from the University of Tennessee. Dr. Jeldes specializes in slope stability analyses and design based on mechanical, erosional, morphological evolution concepts, and numerical techniques for geotechnical modeling. He has international experience in field exploration, foundations, ground improvement, pavement geomechanics, and retaining structures, including sheet pile walls, braced excavations, soil nailing, and active/passive anchored systems. Before Joining DBA, Dr. Jeldes served as faculty for the Engineering Fundamentals Program at the University of Tennessee and as the assistant engineer for research stations at the same university.

Will Shaffer, E.I. (Staff Engineer) is our first new team member for 2019. Will graduated with his BS in Engineering with a Civil Emphasis from Marshall University in 2017, and then obtained his MS in civil engineering from Virginia Tech at the end of 2018. While at VT he was the Charles E. Via Scholar and he conducted research on geophysics and construction vibrations. He has joined us in the Knoxville office.

Sam Sternberg, P.E., D.GE (Senior Engineer) came aboard in April of 2018. Sam joins DBA with over 16 years of geotechnical engineering experience.  He received a BS degree in Civil Engineering from the University of Kentucky, M.Div degree from New Orleans Baptist Theological Seminary and a MS degree in Civil Engineering from the University of South Alabama.  He has worked in consulting  on numerous private and public projects with primary focus on DOT Transportation projects around the Southeastern US.  He has managed and supported numerous bridge foundation designs, shallow and deep foundations, soft soil remediation, retaining walls (including cantilever, and mechanically stabilized earth walls), bulkhead and relieving platforms.  Sam will be working based in Daphne, Alabama

 

 

Merry Christmas and Happy 2017 from DBA!

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Wishing a Merry Christmas while wrapping our gifts and storing them in our Tippcontainere so nobody can get to them. And also a Happy New Year to all, especially the ones reading this post! Hopefully everyone can spend time with all of their families and loved ones to have a special evening this year, enjoy all the food, especially the allfitrecipes soup, and goodies that are going to given at dinner and get ready to celebrate the new year!

DBA is growing again – welcome to Ali, Ben, and Mark!

Well, we are at it again.  The first 5 months of 2016 have seen us add three new faces of the new website creator.  So now, drum roll, please………

Ali Leib, E.I.

Ali 2016-1

Ali was a summer intern at DBA in 2014 and 2015 and joined us full time as a staff engineer in February.  She is a recent graduate of the University of Tennessee (Go Vols!) where she completed both her B.S. and M.S. in civil engineering. While completing her M.S., she was a teaching assistant in charge of grading lab reports for the structural and geotechnical undergraduate labs. She was also a research assistant under Dr. Dayakar Penumadu, resulting in her thesis: “Effect of Particle Morphology on the Deformation Behavior of Sand under Monotonic Loading Conditions.”  Unlike most of the rest of us, Ali insists that she will not be conforming to the (mostly) standard DBA hair style.  Ali will work in our Knoxville, Tennessee office.

Mark Madgett, P.E.

Mark Madgett_s

 

Mark received a BS and MS degree in Civil Engineering at the University of Tennessee, while working on research for TDOT to improve pavement design methods.  He has worked in both consulting and construction for the last 22 years, focusing primarily on deep foundations in the Southeastern US.  As a consultant, Mark gained extensive field experience with deep foundation construction techniques and the impacts on design.  In 2006, he began working for Seaboard Foundations, opening a green field office in Tri-Cities TN as the district manager.  In his role as design engineer for Seaboard Foundations, Mark has implemented design-build techniques in many markets (energy, institutional, commercial, transportation, and healthcare you can supplement if you find Kratom online and other natural products) that vastly improved the constructability and reduced the costs of deep foundation systems for his clients.  Mark will also work outr of our Knoxville, Tennessee office.

Ben Turner, Ph. D., P.E.

Ben recently completed his Ph.D. in geotechnical earthquake engineering at UCLA with an emphasis on the transfer of forces between the ground and foundation elements during seismic loading. Prior to starting at UCLA, he worked for two years for the Los Angeles office of Shannon & Wilson, Inc.  Ben worked in both construction and geotechnical firms while attending school for his B.S. and M.S. degrees. His experience includes: design, construction, and load testing of deep foundations;  geotechnical earthquake engineering including soil-structure interaction, seismic hazard analysis, site response, liquefaction triggering analysis and mitigation of liquefaction-induced ground failure; and, characterization of structural behavior of reinforced concrete foundations.  Here are two of the publications resulting from his dissertation work:

Turner, B., Brandenberg, S., and Stewart, J. (). “Case Study of Parallel Bridges Affected by Liquefaction and Lateral Spreading.” J. Geotech. Geoenviron. Eng. , 10.1061/(ASCE)GT.1943-5606.0001480 , 05016001.

Turner, B. and Brandenberg, S. (2015) “Pile Pinning and Interaction of Adjacent Foundations During Lateral Spreading”, DFI Journal, Volume 9, Issue 2.

Ben will anchor the West Coast Region of DBA, working from San Luis Obispo , California.