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;
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.”
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.”
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.
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.
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
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!
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 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 notbe conforming to the (mostly) standard DBA hair style. Ali will work in our Knoxville, Tennessee office.
Mark Madgett, P.E.
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:
Construction of drilled shafts continues as the superstructure begins to emerge over the skyline between Elizabeth, NJ and Staten Island, NY. The new bridge will be a dual-span 1,983-ft long cable-stayed bridge with approach spans of over 2,500 ft on each side. The bridge is supported on over 200 drilled shaft foundations ranging in diameter from 4.5 ft to 10 ft and socketed into Passaic Formation siltstone.
The GBR is a Public-Private Partnership (P3) that represents a major milestone for the PANYNJ in its distinguished history of bridge building in the greater New York City metropolitan area. The existing Goethals Bridge along with the Outerbridge Crossing and the Bayonne Bridge comprise the three Port Authority bridges connecting Staten Island with New Jersey. The Goethals Bridge and the Outerbridge Crossing are cantilever truss structures and both opened on the same day in 1928. They were designed by J.A.L. Waddell under the supervision of the eminent engineer Othmar H. Ammann (1879-1965), who was the designer of many other iconic bridges in the NY City area including the Bayonne Bridge (1931), the George Washington Bridge (1931), and the Verrazano Narrows Bridge (1964). The designer of record for the replacement Goethals Bridge is Parsons Corporation, which is the successor firm of Robinson & Steinman, whose principal David B. Steinman was also a notable NY area bridge designer and a contemporary and rival of O.H. Ammann.
Each main pylon tower of the GBR is supported on a group of six 9-ft diameter drilled shafts and each anchor pier is supported by two 10-ft diameter shafts. Approach piers are two-column bents with each column supported on a rock-socketed drilled shaft.
DBA is the foundation design engineer of record and this project provides an example of how rock-socketed drilled shafts can provide a reliable and cost-effective means of supporting a major bridge by taking advantage of the high resistances that can be achieved. Key factors involved in taking advantage of rock sockets for this project were: (1) load testing to demonstrate high axial resistances (>30 ksf side resistance and >300 ksf base resistance), (2) utilization of all relevant construction QC/QA tools to ensure that rock sockets are constructed in a manner that is consistent with construction of the load-tested shafts that provide the basis of the design, (3) close collaboration between all members of the design-build team, and (4) adequate subsurface characterization, especially a thorough characterization of rock characteristics and their effect on socket resistances. Load testing for this project demonstrates that side and base resistances can be used in combination to design rock socketed shafts for axial loading. This approach avoids the use of unnecessarily deep sockets, thereby minimizing the associated construction risks and costs.
The Transportation Research Board (TRB) has released a synthesis report prepared by Dan and Robert on large diameter piles: NCHRP Synthesis 478, Design and Load Testing of Large Diameter Open-Ended Driven Piles. The report is a summary of the state of practice with regard to Large Diameter Open-Ended Piles (LDOEPs) in the transportation industry. We conducted a survey of state DOTs as well as interviews with private practitioners to summarize current practices as well as recommend best practices with regard to the selection, design, installation, and testing of LDOEPs. Several state DOTs are using LDOEPs more regularly where large foundation loads may exist and/or the piles are subject to significant unsupported length due to scour, liquefaction, or very weak surficial soils. Marine construction conditions also favor the use of these piles, particularly where pile bents might be employed to eliminate footings.
You can download a PDF of the report or purchase a hard copy at the link below.
DBA has been working on an exciting new project currently under construction in downtown Sacramento, California: the new Sacramento Arena, known as the Entertainment and Sports Center (ESC). The ESC will be a multi-use, publicly owned indoor arena. The Sacramento Kings will be the primary tenant and the arena is expected to host other indoor sports and music concerts, as well. Once completed, the ESC will replace Sleep Train Arena as the home of the Kings. According to Kings Chairman Vivek Ranadive, the 17,500-seat arena will be “one of the most iconic structures on the planet … It’s going to put Sacramento on the world map.”
Turner Construction is the head of development for the new arena. Malcolm Drilling Company was awarded the contract to design and construct the foundation system. DBA worked closely with Malcolm to design Omega piles (a drilled and grouted displacement pile) to serve as the foundations for the new arena. The site presented unique design challenges, including liquefiable soil conditions and existing deep foundations from the demolished portion of the Downtown Plaza.
DBA’s design incorporates 18” and 24” Omega piles. An extensive site-specific load test program was performed to determine the axial resistances of the piles. Eight test piles were instrumented with strain gauges to measure the load distribution in the piles. Supplemental cone penetration testing was performed following load testing to better correlate the load test results with the subsurface conditions.
The piles were designed to resist ground motions from seismic events using site-specific ground curvature data developed by Pacific Engineering and Analysis. The piles were designed to resist the curvature at the anticipated pile section with only a single center reinforcing bar, eliminating the need to extend the entire cage to the bottom of the pile. This detail in the design is very important to ease the pile installation for the site conditions.
The final design incorporates a total of 952 piles to support the arena structure (346 18” dia. Piles and 606 24” dia. piles). The new arena is estimated to cost $477 million, with $255 million of that being funded by the City of Sacramento. The rest of the arena ($222 million) will be funded by the Sacramento Kings. Construction began October 29, 2014 and is planned to be completed by October of 2016.