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By Hannah Lezzoni, Morgan NeSmith

The Augered Cast-in-Place and Drilled Displacement Pile Committee has historically been one of the most active and engaged DFI committees and has performed or spearheaded a number of research projects via the DFI Committee Project Fund (CPF). The authors have had the privilege of being either past or current committee chairs and have been involved in the performance of most of these projects since the fund's inception. The following is a historical overview of the committee's projects and their outcomes.

Nov 1, 2023

By Rob Jameson

"San Francisco is 49 square miles surrounded by reality." So said Paul Kantner of the local '60s icons, Jefferson Airplane, and his words have still held true. The rate, scale and complexity of recent construction in this city has been remarkable, even compared to the Gold Rush or reconstruction after the 1906 earthquake. This article will address developments in soil mixing in San Francisco since 2011, and how the marked settlement of a downtown high rise has influenced this booming construction market.

Jul 1, 2022

By Kyle L. Murrell

Along the southeast United States coast, clayey silt and silty clay marine formations may cause pile installation and integrity problems. More specifically, excess pore pressures which develop in these soils during driving can cause high displacement piles to rebound or ?bounce?. Bounce is defined as a large (¾-in. to more than 1-in.) downward pile displacement during the hammer blow with little to no net displacement at the end of the blow. Pile bounce can generate damaging tension stresses and result in inefficient pile installation. A case history is presented where pile bounce was observed during the installation of 20-in. square ?high displacement? prestressed concrete piles which support a new ferry terminal in coastal North Carolina. High-strain dynamic pile testing was performed during test pile installation to evaluate driving stresses, pile capacities, and hammer performance. During and after installation of numerous production piles, circumferential cracking was observed on some of the piles. Additional high-strain dynamic pile testing was performed on two piles installed with a hammer having a heavier ram than the initial hammer. The new driving system generated lower tension stresses and installed the 20-in. piles more efficiently. Low-strain integrity testing was performed on the piles to qualitatively assess the cracks and locate any unidentified cracks. The low-strain testing was performed on piles installed at least a week prior to testing and on piles installed immediately prior to testing. When low-strain testing was performed immediately after pile installation before dissipation of excess pore pressures, pile integrity could be evaluated to depths of at least 12 pile diameters deeper than when performed weeks after installation.

Jan 1, 2008

"Boston’s Central Artery passes beneath nine active railroad tracks carrying commuter and Amtrak trains into South Station, the City's busiest rail terminal. These railroad operations had to remain in service throughout the construction of the “Big Dig”. The solution was to jack the tunnel under the tracks, rather than build the tunnel by more conventional means.Jacking of utility pipes is fairly common, but jacking boxes as big as a highway had never been done in North America, until the Big Dig came along.Soil freezing was decided upon as a means of stabilizing the soil under the tracks. This allows the tunnels to be jacked into place without soil caving when the soil is excavated at the leading face of the advancing tunnel boxes. Hundreds of pipes were driven into the ground between the tracks. Inside the steel pipes were smaller plastic pipes. A freezing plant near the railroad tracks pumped refrigerated brine into the inner plastic pipes. The brine ran out the bottom of the inner pipe, flowed up to the top inside the outer pipe, and was re-circulated to the freezing plant and back again into the ground. Over several weeks the circulating brine drew the heat out of the soil little by little, and froze the ground outward from the pipes. Soil FreezingThe plan required the construction of jacking pits in which the tunnel boxes could be constructed, and from which they could be jacked forward to their final locations, as described in the accompanying article. Once the jacking pit was built and the tunnel box constructed inside the pit, crews made an opening in the headwall of the pit to allow passage of the tunnel sections, excavated about three feet of the frozen soil, pushed the tunnel box ahead, and repeated the procedure again and again."

Jan 1, 2003

By Christian L. Escalera

Over seven years ago, on October 29, 2012, Superstorm Sandy pummeled the Northeast of the United States inflicting heavy damage on New York City Transit’s (NYCT) system. Since then, NYCT has been methodically rehabilitating and hardening its assets to upgrade service and prevent future impacts caused by similar devasting storm surges. Part of these resiliency efforts, NYCT’s 207th St Yard Project is one of many projects that make up the Sandy Repair and Flood Mitigation Program. The work to be performed on the 207th Street Project includes building a perimeter Floodwall along the Harlem River, extending up 215th Street and 9th Avenue with the intent of having the ability to withstand a 500 Year Storm flooding event. The original 1,535 lineal feet of the marine side floodwall design consisted of 937 each W40x235 H-Piles continuously welded to PS 27.5 flat sheet to form an interlocked and composite steel seawall that would protect the NYCT 207th Yard from a storm surge of the Harlem River. However, after the Contract was awarded and a Notice to Proceed was issued, Walsh Construction Company II (WCCII) partnered with Mueser Rutledge Consulting Engineers (MRCE) to propose a redesign of the marine wall section as a Value Engineering Change Proposal (VECP). This VEP redesign is comprised of 279 each 54in Diameter Steel Pipe Piles that are interconnected with continuously welded PZ 35 sheet piles interlocks. The intent of the VEP was to provide a cost savings that could be shared by both parties as well as alleviate some constructability and alignment control concerns that WCCII had expressed to NYCT. The VEP allowed WCCII to substantially lower the total cost which was shared between NYCT and WCCII.

By A. J. Metz, Roberto Nevarez

One popular method to stabilize slopes is the use of deep foundation elements to support lateral loads from an unstable soil or rock mass. Drilled deep foundation elements are often selected due to local availability of equipment, access concerns, cost considerations and post-construction aesthetics. Often, one or more rows of deep foundation elements are installed running parallel to the slope. The elements in each row may or may not be connected through a cap beam. They work primarily in bending, and resist slope movement by transferring the earth pressures down below the potential slip surface. Design of these systems considers the effect of arching

Nov 1, 2023

By Kelvin Lo, Erwin Oh, Darren Newel

The use of interface elements is widespread in most numerical methods to separate the structural elements from soil elements. It allows slipping and gapping or overlapping between the two media in contact with highly distinct deformability characteristics, such as piles and retaining walls. However, many existing analytical methods still assume no pile-soil slipping before failure in axially loaded piles. This paper attempts to compare the slipping and non-slipping analytical models by introducing an interface with a virtual thickness. Results show that both have different load-displacement characteristics when comparing to the measured data. The non-slipping model would result in a stiffer load-displacement curve if the same input stiffness parameters applied to both models. Different procedures to calibration the input stiffness parameters in slipping and non-slipping models are recommended.

By Thomas Kennedy, Michael Bennett

"History never repeats itself, but it often rhymes." The old aphorism reflects how the study of the past may, perhaps, be most widely valued when it can be used to improve current and future decision making. The education the authors received as geotechnical graduate students certainly impressed upon them the importance of recognizing that not all wisdom is necessarily new. Much of their graduate coursework involved reading technical papers that had introduced concepts of outstanding historical significance in the field, such as pore pressure coefficients, stress paths, and the stress history and nor- malized soil engineering model. These papers gave the authors both respect for and interest in the historical develop- ment of the field. After graduation, the authors furthered and deepened this interest by continuing to expand their knowledge of the profession through both experience in practice and the review of additional literature.

Jan 1, 2023

By Patrick T, David K. Miller

Driven piles are an effective and cost-efficient deep foundation method; however, when piles are driven near existing buildings and improvements, vibrations must be controlled to non-damaging levels. Monitoring of adjacent structures is important for loss prevention, specification compliance, and public relations. The fundamentals of ground vibrations, including particle velocity, acceleration, displacement and frequency will be discussed. Types of pile driving and the ground vibrations that result will be summarized. Industry standards for safe vibration levels for various structures (residential, commercial, industrial, historic, utilities) will be reviewed. The paper/presentation will include a discussion of soil settlement from pile driving vibrations and case histories of observed settlements. Methods for calculating vibration amplitudes and frequencies will be presented. Best practices for monitoring and controlling ground vibrations, including available state-of-the art equipment, will be outlined. The paper/presentation will conclude with steps for designing and implementing a monitoring and control program.

By Michal Topolnicki

Deep Mixing Series: This article is the second keynote highlighted from DFI's virtual Deep Mixing Conference in 2021, for which Topolnicki served as a committeee co-chair Polish applications of deep soil mixing (DSM) technology occupy a leading position in Europe. That includes use for road and railway embankments, bridges, residential and industrial build- ings, silos, commercial centers, slabs, car parks and storage yards, excavation supports and cut-off walls. In fact, more than 350 road and railway viaducts and 200 wind turbines have been founded nationally on DSM columns, which are firsts on an international scale. This represents more than 1,200 imple- mentations by the Polish geotechnical industry. Considering the need to update DSM design recommendations, this article will attempt to summarize the best practices of wet DSM design and implementation, in particular. It draws on 20 years of experience and will high- light the properties and principles of the design of stabilized soil and lessons learned. Case studies are included to fur- ther understanding of the careful con- siderations needed with this technology.

Apr 1, 2022

By Morgan NeSmith

The Port of Palm Beach is a full-service landlord port in Riviera Beach, Florida. The port and its tenants process more than $14 billion in commodities. About 80% of these are exports, which makes the Port of Palm Beach one of only 16 "Export Ports" in the U.S. More than 2.5 million tons of cargo move through the port every year. Ozinga, a fourth-generation family- owned construction materials company, has supplied ready-mix concrete for commercial, residential, public works, landscaping and excavation projects from several of its Florida locations. It planned to build a one-of-a-kind cement storage facility to receive and store international ship- ments of cement for transport to other facilities for the production of ready- mix concrete. Dome Technology, of Idaho Falls, Idaho, designed and constructed the 125 ft (38 m) diameter storage facility. The design and working volume of cement for the facility was just under 27,000 cu ft (765 m3). The design loads required to be supported by the foundation system are shown in this table:

Apr 1, 2023

By Kirty Dave

Foundations in any contract are the most uncertain parts of the contract and most of the "Construction-Contract-Disputes" are either directly related to foundations or arise as 'Side-effects of changes in promises related to foundations. Foundation Engineering is defined as ' The art of selection, designing and constructing the elements that transfer the weight of structure to the underlying Soil or Rock." (Ralph B. Perk). This art started becoming a science since 1920, when scientific efforts to determine the behaviour of sub-surface materials were made. The art and science merged to give new techniques and the science started dominating the field as more and more refinement came in techniques to predict more accurately the characteristics of the sub-surface elements. Inspite of good thorough investigations and design, the contractual promises drafted could leave some room for differences between the parties and above all the prudency expected of both the parties may fall short of the expectations raised in the contract. This may give rise to disputes which may need to be resolved as per principles of law. This paper attempts to initiate a dialogue amongst Foundations-Engineers and Contractors as to how do we minimise the differences arising out of or related to contracts concerning "Foundations".

Jan 1, 1996

By John Y. L Chen

This paper presents full-scale instrumented pile static compressive and tensile load tests to be conducted in the area of Pearl Harbor, Hawaii. Thousands of piles have been installed to support the existing piers and wharves in the Pearl Harbor area. Due to the absence of bedrock within practical depths, most of the piles use combined friction and end bearing. A new 925 feet (282 meters) long and 50 feet (12 meters) wide reinforced concrete wharf supported on pile foundation is planned. This paper will present results of soil investigation, laboratory testing, dynamic load tests during indictor pile driving and static pile load tests. The subsurface conditions consist of soft harbor sediment, young alluvium deposit, volcanic tuff rock formation and stiff old alluvium deposit. The load test piles consist of 20-inch (508 mm) square and 24-inch (610 mm) octagonal pre-stressed, pre-cast concrete pile and instrumented with embedded strain gauges. The length of the piles ranges from about 50 to 125 feet (15 to 38 meters). The test pile program consists of probing, driving indictor piles, dynamic load tests during indictor pile driving and static load tests. The standard loading procedure method was used during static pile load tests.

Jan 1, 2002

By David White

When finished (projected completion in 2016) the Hong Kong-Zhuhai-Macau Bridge Project will comprise three cable-stayed span bridges and a 4.15 mile immersed tube tunnel - linking Hong Kong to Macau and the mainland Chinese city of Zhuhai. The design included two artificial Islands to serve as the transition structures for the tunnel to bridges, entailing a massive seaborne land reclamation project, and the use of thousands of sheet piles, and man-hours. The challenges of driving individual steel sheet in 100? of water are well known, let alone in the open waters of the South China Sea. In 2010 a joint effort between American Piledriving Equipment (APE) and Allnamics Pile Testing Experts convinced the Chinese contractor First Harbor Marine Group China that a massive multi-vibro hammer can be used to drive 130? long, 72? diameter steel pipe piles weighing 662 US tons each into the sea bed of the South China Sea for the Hong Kong - Zhuhai - Macau bridge artificial islands. Combining APE?s hammer design, production and operation know-how with the pile driving simulation and installation know-how of Allnamics made it possible to show the feasibility of driving these gigantic piles into bottom of the sea to the required depth.

By David White

"When finished (projected completion in 2016) the Hong Kong-Zhuhai-Macau Bridge Project will comprise three cable-stayed span bridges and a 4.15 mile immersed tube tunnel - linking Hong Kong to Macau and the mainland Chinese city of Zhuhai. The design included two artificial Islands to serve as the transition structures for the tunnel to bridges, entailing a massive seaborne land reclamation project, and the use of thousands of sheet piles, and man-hours. The challenges of driving individual steel sheet in 100’ of water are well known, let alone in the open waters of the South China Sea.In 2010 a joint effort between American Piledriving Equipment (APE) and Allnamics Pile Testing Experts convinced the Chinese contractor First Harbor Marine Group China that a massive multi-vibro hammer can be used to drive 130’ long, 72’ diameter steel pipe piles weighing 662 US tons each into the sea bed of the South China Sea for the Hong Kong - Zhuhai - Macau bridge artificial islands. Combining APE’s hammer design, production and operation know-how with the pile driving simulation and installation know-how of Allnamics made it possible to show the feasibility of driving these gigantic piles into bottom of the sea to the required depth.INTRODUCTIONThe challenges of driving individual steel sheets in deep water are well known, let alone in the open waters of the South China Sea. Often the challenges of construction are overcome with engineering or equipment. The challenges of China’s Hong Kong-Zhuhai-Macau Bridge, on the drawing board since 1983, were to overcome both. The challenges of overcoming the skepticism of the Chinese Engineering community would be another story.The finished project will comprise three cablestayed span bridges and a 4.15 mile immersed tube tunnel linking Hong Kong on an eastern span to the China mainland cities of Zhuhai and Macau via two western spans."

Jan 1, 2017

By R. K. M. Bhandari

Geotechnical investigation for a LPG plant located in Assam state - an area of high seisimicty - revealed a layer of loose to medium silty sand susceptible to liquefaction at some depth below the finished ground surface. Liquefaction analyses were carried out using simplified Seed's approach as well as considering the progressive buildup of pore pressures with cyclic earthquake loading. Seismic settlements were computed for areas where the analysis indicated partial liquefaction. Pile foundations in areas where complete liquefaction was indicated, were treated with gravel drains to prevent buildup of pore pressures. The paper presents and discusses the liquefaction analyses, effect of non-liquefiable overburden soil on the liquefaction potential of the silty sand and the remedial measures that have been taken to ensure safety of the pile foundations in transmitting vertical and lateral loads.

Jan 1, 1996

This paper summarizes seven years of Italian ex­perience with the use of large calibration chambers for the calibration, under closely controlled stress and strain conditions, of some in situ testing devices which are used in sand deposits. At the present time two calibration chambers are operating in Italy, one at E.N.E.L.-C.R.I.S. (Milan) (*) and the other at I.S.M.E.S. (Berga­mo) (**). Both chambers can accomodate cylindrical samples 1.2 m in diameter and 1.5 m in height. A detailed description of these chambers can be found in Bellotti, et. al (1982).

Jan 1, 1987

By Arash Khosravifar

One of our research thrusts at Portland State University (PSU) centers on developing design guidelines for pile foundations in liquefiable, laterally spreading grounds. This research has been primarily sponsored by the DFI Committee Project Fund (CPF) program through four awards, totaling nearly $240,000 in financial support. DFI contributed half of this financial support, while the other half was contributed in-kind by PSU and DFI Project Advisory Board members. Leveraging the CPF funds, we secured an additional $550,000 in financial support from the National Science. Foundation (NSF), which has enabled our research group to continue exploring this topic and contributing to the broader engineering community's understanding of the behavior of pile foundations in liquefiable soils. The CPF funds have fostered collaborations with practitioners and researchers beyond PSU. Notable examples include collaborative research involving data from five large-scale centrifuge tests on pile-supported wharves by Steve Dickenson, Ph.D., New Albion Geotechnical; Nason McCullough, Ph.D., Jacobs Engineering and Scott Schlechter, Geotechnical Resources, as well as 1-g shake table tests of bridge pile shafts conducted by Professors Ahmed Elgamal, Ph.D., and Ahmed Ebeido, Ph.D., of the University of California, San Diego. In addition to these collaborations, our research has benefited from industry-university partnerships formed through the involvement of DFI Project Advisory Board members. Their support and feedback ensure that our research products are practical and imple- mentable in real-world projects. The impact of the CPF funds extends to supporting graduate students' theses, which were the basis for 17 technical publications. Some of these publications are expected to have a significant impact on the industry. For instance, our 2018 DFI Journal paper, co-authored by former master's student Jonathan Nasr, cur- rently with the Army Corps of Engineers, has been cited in the 2022 British Columbia Supplement to Canadian Highway Bridge Design Code S6:19. A noteworthy product of our study is a step-by-step design procedure for pile- supported wharf structures subjected to the combined effects of lateral spreading and inertial loads, outlined in a 2022 American Society of Civil Engineers' (ASCE) Journal of Geotechnical and Geo- environmental Engineering paper co- authored by former doctoral student Milad Souri, Ph.D., PE, Geotechnical Resources.

Nov 1, 2023