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By Derrick D. Dasenbrock

Three piers of a new river bridge are supported on 1.067 m diameter open-end steel pipe piles. At time of drive, and after pile re-strikes, high-strain dynamic capacity values at plan tip elevations, were as low as 23% of design requirements. Pile lengths were extended 20% to 40% deeper than planned at two piers, driving to rock, impacting both the project cost and schedule. The significant discrepancy between predicted and observed capacity was investigated through a series of coordinated dynamic tests; a full-scale test pile was installed and monitored over 221 days by both dynamic and quasi-static methods. Unusually slow strength gains were observed by dynamic monitoring on all piles installed at the site. CPT soundings were advanced at the test pile and through the pile interior to investigate the soil plug. High-strain dynamic methods were found to have significant limitations in properly assessing the long-term capacity of large-diameter open-end pipe piles during driving and short-term pile re-strikes. As the benefits of large diameter high-capacity open-end pipe piles are numerous, the geotechnical community needs to address appropriate construction monitoring and control of these foundation types to take full advantage of these systems. An improved understanding of the physical effects of pile installation and the impact on soil strength assessment while driving and long term soil strength gain should be developed and incorporated into both design and monitoring procedures to avoid either unsafe or needlessly costly designs.

Jan 1, 2006

By Jim Glider, Noah Miner

The Gordie Howe International Bridge is a project to build a cable-stayed bridge and border crossing across the Detroit River. With a span length of 2,800-ft (853.4 meters), the Gordie Howe International Bridge will have the longest main span of any cable-stayed bridge in North America. Each tower has two legs that are supported by six drilled shafts each for a total of 12. The tower shafts are 9.84 feet in diameter (3-m) and extend well into bedrock. 17 each, 6.6 feet (2-m) drilled shafts were built to support the aging river bulkhead and replace shipping bollards. In addition to shallow groundwater fed by the Detroit River, artesian conditions at depth result in a water head that is approximately 17.2-ft (5.2-m) above surface. At 95-ft (29-m) below grade Dundee Limestone, of the Detroit River Group, is moderately weathered and fracture density decreases with depth. The Dundee Limestone strength ranges from 8-ksi (55.1-MPa) to 12-ksi (82-MPa) and may carry hydrogen sulfide in fractures. Working through casing that sticks three stories out of the ground is less than ideal, but was necessary to maintain a positive fluid head and prevent artesian-related quality issues. The sheer scale of the bridge forces required a load test configuration that could impart an equivalent static load of over 38,000,000 pounds (170-MN). A suite of QA/QC tests was developed to ensure the shafts would meet the project plans and specifications to include critical base cleanliness criteria. Interesting CSL and TIP results obtained highlight the strengths and weaknesses of each test method. Cleaning drilling fluids with a centrifuge allowed recycling of product and reduced exposure to environmental contaminate exposure. Having large construction equipment working next to the river presented challenges in working pad design. A driven pile system was developed to support high oscillator forces and protect the aging seawall.

Sep 8, 2021

By Pawan L. Sethi

Design and construction of deep foundations and basements is increasingly becoming more complex, as the density and frequency of urban development increases. This growth brings various associated challenges in the form of design considerations and construction challenges. This paper discusses some of the challenges routinely encountered as well as some specific complications in this area, based on author’s experience gained through exposure as specialist contractor (designer), consultant and specialist consultant, along with some information on how these challenges were overcome. The paper highlights some of the key aspects of design coordination and importance of having an awareness of the overall perspective. Examples will be used to illustrate practical problems and the approaches used to respond.

Nov 1, 2022

By W. L. Chong, Y. Zou

There are many types of Earth Retention Systems (ERS) available in the market where more than one method can be a feasible solution for a project. This paper examines the design and construct process of a project in Dee Why, NSW using a hybrid ERS comprising contiguous piles with jet grout infill. The development comprises a deep basement and mixed-use urban superstructure. The site is located in an area of variable ground conditions, high ground water table and in proximity to existing buildings with multi-level basements. This paper details a comprehensive assessment of the geological conditions and strategies adopted to better understand the effectiveness of the proposed product and to minimise the associated risks of the proposed solution. This involved conducting additional geotechnical investigation, extensive numerical modelling and in-situ monitoring of the movements and the performance of the walls. A monitoring regime consisting of inclinometers, survey points on capping beam and prisms on the neighbouring buildings and roads surrounding shoring wall was implemented. The monitoring results were back-analysed using computer software WALLAP, Plaxis–2D and Plaxis–3D for the post-construction examinations. This paper details the effectiveness and advantages of a hybrid ERS using contiguous piles with jet grout infill.

Nov 1, 2022

By Alexander Filotti, Stanley Merjan

"Abstract. The paper shows the benefits and accomplishments of this relatively new but established product on the pile foundations market in the United States. The first part of the paper describes general aspects of the design, construction, and geotechnical capacity (designed and in situ) of Tapertube piles. The qualities resulting from the design and manufacturing of the Tapertube pile will be presented first.The second part of the paper describes the installation of Tapertube piles for an addition to Terminal One at JFK International Airport and The Edge development. A carbon print analysis for both projects is developed using the EFFC-DFI carbon print calculator. For the JFK project the benefits of using BIM in redesigning the project for Tapertube piles are explored.General description.The tapertube pile consists of a tapered tubular bottom section attached to a conventional pipe extension. The 50 ksi steel for the taper is mechanically folded into a polygonal cross-section (usually 12-sided) with a longitudinal welded seam. The tapers are fabricated in many sizes with bottom diameters varying from 8 to 14 inches, top diameters from 12 to 20 inches, lengths from 10 to 35 feet, and steel thicknesses from 3/16 to 1/2 inch. A conical steel shoe or a flat plate is welded to the bottom of the taper and the top of the taper is circularized to match the outside diameter of the pipe extension. The inclination of the tapers is generally between 1.5% and 2.5%.The pipe extension is fully butt welded to the taper and has the necessary length for the pile to develop the requisite capacity. Concrete fill for the piles is generally 4,000 p.s.i. or more. Typically the piles are shopassembled and shipped to jobsites in lengths to 80 feet."

Jan 1, 2014

By Paul Doherty

Expansion of the global piling industry has been coupled with significant research efforts investigating the mechanisms controlling pile capacity. Static pile design has transitioned from total stress approaches toward effective stress design, with associated improvements in predicting pile performance. As a result, the available literature is heavily skewed toward static capacity prediction. However, when considering piles offshore, the majority of loading is not static but highly variable and cyclic in nature. This paper outlines the additional factors that require consideration for cyclic pile design, including elevated loading rates, cyclic displacements and capacity degradation. A review of the literature identified a number of cyclic pile testing programs which are collated in this paper. General trends are established through comparison of the tests within the database and the conditions where cyclic loading is most likely to be a concern are identified. In particular, loading conditions which involve full plastic shear reversals are seen to cause the most extreme cyclic damage, with the degraded capacity as low as 31% of the precyclic static capacity. The underlying mechanisms which can result in cyclic damage are explored, with particular attention given to the pore pressure response, radial stresses, shear transfer and particle reorientation.

Jan 1, 2009

By Gerald Verbeek, Erick Baziw

Dynamic soil analysis (DSA) in geotechnical practice is intimately related to the capability of measuring the necessary soil properties of shear modulus and absorption. In DSA the methods of analysis are based upon the stress-deformation response of soils due to imposed shear strains. Typically the soil profile is numerically modeled as linear visco-elastic system. This technique is referred to as the Equivalent Linear (EL) method, and it requires the specification of the input parameters of low-strain (<10-5) shear modulus, modulus reduction, and the equivalent viscous damping ratio, which is directly related to the soil absorption value. Downhole seismic testing (DST) has proven to be a very accurate tool for estimating low strain shear modulus values as long as source wave raypaths are taken into account, especially for near-surface investigations. DST has also been utilized to estimate low-strain interval absorption values. In these cases standard frequency domain absorption estimation algorithms (such as the spectral ratio technique) are utilized where it is assumed that the source waves are traveling along the same travel path, which is obviously not the case for near surface DST investigations. This paper outlines a unique DST absorption estimation methodology, which is carried out in the time domain and takes into account source wave travel paths. 1. INTRODUCTION There is considerable interest in methods of geotechnical in-situ engineering that provide accurate estimates of the shear wave velocity and the associated absorption values in the ground, since these parameters form the core of mathematical theorems to describe the elasticity/plasticity of soils and they are used to predict the soil response (settlement, liquefaction or failure) to imposed loads (whether from foundations, heavy equipment, earthquakes or explosions).

Jan 1, 2019

By Fritz J. Klingler

From site demolition, to design, to construction, Detroit&apos;s new Tiger Stadium project is required to be completed within a short 2 ½ years from award of the design-build contract. Such extreme schedule requirements together with somewhat difficult ground conditions at the site, resulted in several challenges in the design and construction of the deep foundation system for the stadium. During the geotechnical investigation, an intermittent water bearing sand layer was encountered overlying the hardpan at the site. As a result, some concern developed regarding the potential for collapse of caisson bells within this layer, as well as the potential for flooding of the caissons during drilling. Although sand and/or ground water was encountered within about half of the caissons, standard drilling and belling methods were used, and adverse conditions were controlled in almost all cases through expeditious drilling, inspection and concreting of the caissons. This paper will present a summary of the ground conditions, design and specification requirements, and construction methods used to successfully install the caissons for this project.

Jan 1, 1999

By Hessam Yazdani

In comparison to the conventional piled foundations, the piled-raft foundations provide a more economical solution to support high-rise buildings constructed on soft soils. In this type of foundations, the bearing capacity of the underlying soil is taken into account to support the superstructure loads and the piles are placed to control both the total and differential settlements of the superstructure. Currently, there is not a standard and worldwide acceptable approach to select the location of the piles and most of piled-raft foundations are designed based on the experience of designers. Therefore, particular attention should be given to the optimal design of this type of foundations in order to minimize the considerable construction costs involved. This paper examines the capability of the ant colony optimization (ACO) algorithm to optimize the piled-raft foundations subjected to static and seismic loadings. The soil-pile interaction is considered by modeling the side and tip resistance components of the piles using the nonlinear Winkler-based p-y and t-z curves in the OpenSees program. The soil-raft interaction is taken into consideration using the Winkler springs beneath the raft. The objective of the optimization problem is to minimize the construction cost of the foundation by taking the configuration and number of the piles as design variables. The side and tip forces of the piles as well as the total and differential settlements of the foundation under the serviceability limit state are considered as the constraints for the optimization problem. Results show that in addition to the type of analysis (linear/nonlinear), the regard or disregard of the soil-pile interaction in the analysis can significantly change the optimal solution. The optimal solutions obtained match the engineering expectations and indicate the effectiveness and capability of the ACO algorithm to minimize the construction cost.

Jan 1, 2013

By Masaaki Terashi

The machine for the hybrid method called JACSMAN is ordinarily a dual shaft machine. Each shaft has augers at three different levels and nozzles for jetting at two different levels. The distance between two shafts may be changed according to the particular requirements. Figure 4 shows single shaft and a treated soil column created by the method. The diameter of the auger is 1.0 m. As the jetting nozzles locate at the periphery of the auger, jetting can achieve the additional treated soil column beyond the diameter of the auger. The diameter of the jetting improvement is fixed at 2.3 m.

Feb 10, 2003

By Fabio Santillán, Mario Mauro, Raffaella Granata

"This paper presents the utilization of slurry walls methods for the recent remediation of three high hazard active dams in the United States. Tuttle Creek Dam, located in Manhattan, KS, required seismic retrofit. To this extent, transverse shear walls were installed on the downstream slope using self-hardening slurry (SHS) to reinforce the liquefiable foundation soils. Herbert Hoover Dike, located around Lake Okeechobee, FL, is subject to potential failure because of internal erosion, piping and slope instability at high water levels. The innovative use of the hydromill equipment with SHS allowed the successful construction of the cutoff wall through heterogeneous soils and rock. At Bolivar Dam, located in Bolivar, OH, under-seepage negatively affects the structural stability of the dam, and a partial seepage barrier wall is required through the upstream slope of the dam. In this case, the Contractor selected the plastic concrete seepage barrier, excavated by a combination of clamshell and hydromill equipment. The main features of the three projects are summarized in Table 1. IntroductionTuttle Creek Dam was constructed by the U.S. Army Corp of Engineers (USACE) on the Big Blue River in North-East Kansas in the 1950s for flood control. Tuttle Creek Dam is a zoned earthfill embankment, 7,500 ft long and about 137 ft high with a crest width of 50 ft (Fig. 1). It is located in an area of moderate seismicity associated with an old continental rift zone located just to the east of the dam. The USACE, under the Dam Safety and Assurance Program, determined the need for remediation. Site investigations and geotechnical analyses identified the upper alluvial foundation sands as being susceptible to liquefaction when subjected to the Maximum Credible Earthquake.In 2005, USACE awarded a construction-manager-at-risk/early Contractor involvement contract. The USACE and the Contractor closely cooperated to identify the most effective technologies, materials and configurations to be used in the remediation. The original remediation design required both the upstream and downstream slope stabilization of liquefiable foundation. Results of refined seismic deformation analyses revealed that the stabilization of the downstream slope and toe was needed to protect the downstream seepage control system and to provide assurance that a liquefaction-induced flow slide would not occur (Stark et al., 2012)."

Jan 1, 2016

By Daniel P. Stare, Lucian P. Spiteri, Christopher M. Hallahan, James C. Myers

Buckeye Lake Dam was substantially remediated between 2015 and 2018 as a result of unacceptable dam safety performance. A permanent seepage cutoff, consisting primarily of a soil mixed cutoff wall (SMCW) with occasional sections of steel sheet piling, was constructed along the dam alignment. Closures were required at the terminus of the soil mix elements with existing structures or coffer cells, and at locations where new sheet piling was constructed parallel to the new soil mixed cutoff wall, creating a short circuit seepage path. The original proposed design to construct these closures included permeation grouting methods with chemical grouts. However, a combination of multiple chemical grout types, multiple grout pipes, and an extensive post-grouting verification program was required to ensure the design intent was achieved. After award of the project, the specialty grouting contractor elected to evaluate jet grouting as an alternative closure construction method. The advantages of the jet grouting option offered potential schedule and cost savings to the project as well as a superior product for seepage reduction, given the mixed soil conditions at the site. This paper presents an examination of the site conditions and project goals for the construction of the proposed closure elements for the rehabilitation of Buckeye Lake Dam. Descriptions of the original and alternative treatment methods are provided, with expected performance results. A description of the relative strengths and deficiencies of each method, as well as the feasibility and constructability of each method is provided. The implementation of the jet grouting program is presented, including a discussion of the design elements, quality control test methods, movement monitoring, and verification test methods. This paper also examines the risks associated with jet grouting and how those risks were mitigated during the grouting operations. HISTORY Buckeye Lake is situated approximately 28 miles east of Columbus, Ohio and is managed and operated by the Ohio Department of Natural Resources (ODNR) as part of the Ohio State Parks system. The lake is impounded by natural features that exist along the south and east banks of the reservoir, and by the embankment structure constructed along the north and west banks of the reservoir (see Fig. 1). The reservoir site was originally a natural swamp and the original purpose of the constructed dam and reservoir was to provide water to the Ohio and Erie Canal System. Several dam alignments and configurations were constructed during its early history; however, the original embankment is comprised of homogeneous earthen fill. The embankment is 15 ft (4.6 m) high and extends 4.1 miles (6.6 km) from the North Shore abutment along the east, continuing to the abutment at Lieb’s Island to the West. Several spillway and outlet structures exist along the embankment alignment. Most noteworthy are Seller’s Spillway and Amil Spillway. Fig. 2 is a Plan View of the embankment alignment and appurtenant structures at Buckeye Lake.

Jan 1, 2019

By D. J. Ketkar

It is a frequent experience to find that the Sub-surface Investigation (S.I.) data is either inadequate or misleading. However, such cases are rarely reported. Nonetheless, the projects suffer on-account of delays, cost-over-runs, disputes and/or compromise of the safety norms. Many times S.I. is considered unnecessary or is carried out as a ritual, mainly due to (i) non-availability of good S.I. agencies, or (ii) absence of Geotechnical consultant, or (iii) shortage of time. Importance of S.I. cannot be over emphasised. Yet the profession is in a state of confusion - mainly because of lack of competent professional agencies and of well-defined roles/responsibilities of the concerned parties. In this paper, some suggestions are made to get better returns from the S.I. activity.

Jan 1, 1996

By L. F. Albert

The paper describes solutions given to foundation problems during the reconstruction of a power plant set on fire, located adjacent to several still Working Units. After a detailed site and laboratory investigation, it was decided that it could be possible to include within the new foundations the preexisting cast in situ driven piles with enlarged base 50 cm in diameter and let them work with new 41 cm driven, cast in situ piles without enlarged base. Demolition of existing caps was carried out with expansive mortar in order to avoid any possible damage to piles, whose actual conditions were checked by several load tests. New piles were designed to support service load by shaft resistance, in order to limit total and differential settlement. When piles had to be driven adjacent to nearby structures, measurements of peak soil particles velocity were carried out while driving piles at decreasing distance from critical locations. By preboring most of the upper clay layer it was possible to reduce within safe limits for structures the induced vibrations.

Jan 1, 1989

By Aly M. Mohammad

State and federal agencies during rehabilitation of existing bridges may require the existing bridges to be evaluated under seismic conditions. If the bridge does not perform under the seismic event, the bridge may require seismic retrofitting. Bridges are classified as: Critical, Essential, and Others according to their importance. Geotechnical considerations play a major role in evaluating the bridge behavior under a seismic event. Subsurface conditions influence the magnitude of ground acceleration and hence the forces and moments on the superstructure. This paper will provide a detailed description of the geotechnical aspects associated with the seismic retrofit evaluation for the 12th Street and 14th Street Viaducts located in Jersey City, New Jersey. The paper will also present a description of the geotechnical investigation program including seismic cross-hole surveys to determine the dynamic soil parameters, including the results of site-specific response spectra for both the 475 and 2475-year events. Liquefaction assessment methodology utilizing an equivalent factor of safety will also be described and the design method used will be summarized. In general, the pile foundation is modeled as 6x6 foundation stiffness matrix with 36 stiffness coefficients at the center of the pile cap. The seismic loading on the foundation is evaluated in a pseudo-static analysis, where the dynamic earthquake-induced loads are presented by static forces and moments. The computer program FB Pier was used to evaluate the foundation stiffness. The moments, axial loads, and shear are input into the FB Pier model. The stiffness of the foundation is determined and the results are then input into the Structural model to determine new forces and displacements. Adjustments are made until the loads are compatible with the stiffness used. The understanding of the geotechnical conditions at the 12th Street and 14th Street Viaducts and the coordination between the Bridge and Geotechnical Engineers were able to provide significant cost saving to the Owner. The Design Engineers were able to retrofit the existing Viaduct foundations with reasonable number of additional piles. It is believed that the results and finding presented in this paper will benefit both the Bridge Engineers and Geotechnical Engineers by highlighting the importance of interaction between the two disciplines.

Jan 1, 2006

By Amy B. Cerato

The application of this study is to use helical anchors as a foundation system for small wind tower (1 ? 10 kW) guyed cables. Helical anchors are currently used to anchor guyed cables of telecommunication and electric towers. However, the increased dynamic vibrations a wind turbine adds to the tower and foundation system under working loads, as well as extreme environmental conditions (e.g., straight line winds, ice load or sudden furling shocks), require additional knowledge about the behavior of helical anchors. These field conditions were simulated in this study by instrumenting a working tower with load cells and 3-axis accelerometers to gather data on wind speed and tower response. These tower responses were then transmitted to the helical anchors through an extensive, large-scale testing program that included monitoring the performance of the helical anchor foundation under dynamic loads, subject to natural variations in both wind regimes, precipitation (water level) and variations in helical anchor geometry. This paper specifically discusses the effects of helical anchor geometry on helical anchor performance under long-term dynamic loads.

Jan 1, 2008

By Ronald D. Boyer

"Early in the design stage of Meadowlands Xanadu, the client’s project director informed me that “after construction, nobody is going to come to Xanadu to see the foundations.” My response was, “Well, that’s good, because the only reason someone would come to see the foundations is if there is a problem with them.” The client’s real message was clear: the money for the project would be better spent on architectural design components and interior finishes that would attract high-end tenants and entertainment seekers. The foundations, however, were challenging. The sheer size of the Xanadu development, the varying depths to rock, the loading conditions associated with the different structures, and the construction sequencing required the use of multiple deep foundation types and specialty foundation contractors. Xanadu, when completed, will consist of over 2.5 million sq ft of entertainment venues, restaurants and retail stores; America’s first i n d o o r s n o w dome; North America’s tallest (287 ft high) Ferris wheel; and four parking decks. Finished grades for Xanadu were essentially within about 1 to 2 ft of existing grades at the site, except for a 5 acre wetlands area, which received about 8 ft of new fill. Before the current construction, the approximate 75-acre Xanadu site was occupied by the Continental Airlines (now Izod) Arena, on-grade parking lots and the wetlands area. The Arena property is part of the New Jersey Sports and Exposition Authority (NJSEA) Meadowlands Sports Complex, which also includes Giants Stadium and the Racetrack, and is located in East Rutherford, N. J. Subsurface ConditionsThe site subsurface conditions include fill materials underlain by organic silt and peat (former marsh deposits or “meadowmat”), varved clay, glacial till and shale bedrock. The Xanadu site had been a marsh until the Sports Complex was created by filling in the early 1970s. The fill consists of dredged materials from Lower New York Harbor imported by hydraulic pipeline from the Hudson River. The fill also includes “historic fill,” defined as nonindigenous material deposited to raise the topographic elevation of a site, such as construction debris and other nonhazardous solid waste, and was generally encountered in thicknesses ranging from 8 ft to 18 ft. Within the previously developed portion of the site, a layer of marsh deposits consisting of peat and organic silt was encountered beneath the fill in thicknesses ranging from two ft to seven ft. Within the existing wetlands area, the marsh deposits were up to 10 ft below existing grade. The varved clay stratum was six ft to 36 ft thick. The depth to shale rock increases from approximately 15 ft near the west side of the site to approximately 80 ft near the south side. Groundwater was tidally influenced and varied from about 6 to 12 feet below both existing and proposed grade."

Jan 1, 2009

By Marcelo Chuaqui

We certainly have the data to back calculate it. I must admit that I haven&apos;t, at the moment my priority is not on what is the stiffness of the jet grout but is making sure that the jet grout is really there. It&apos;s a bit like what Stuart Littlejohn was talking about this morning in terms of grouting on the dams a small window causes a big problem so it&apos;s having the jet grouting there at all, at the moment must have been my focus rather than just what is the stiffness once you&apos;ve got it there.

Feb 10, 2003

By DFI DFI

An Online Conference

By Joel Moskowitz, Jan Cermak

"New York City has unique geologic conditions which must be considered when designing pile foundations. Where shallow foundations are not feasible, the City's subsurface conditions require a variety of deep foundation systems, ranging from high capacity rock socketed piles, to piles end-bearing on bedrock, to friction piles bearing in alluvial or glacial deposits. Pile load testing is essential in confirming pile capacities as pile analyses include assumptions on soil and soil-pile response, and pile driving equipment. Load test results must be interpreted to estimate the long-term pile behavior. Except for lightly loaded driven piles, the New York City Building Code (the Code) requires that pile capacities be confirmed by static load testing. The Code provides the number of static load tests required, test procedures, and acceptance criteria. In the last few decades, methods other than static load testing have been developed including dynamic and rapid (pseudo-static) load tests. Recently, those methods have also been employed on several projects in New York City. The traditional approach to pile load testing in New York City is discussed herein including engineering involved in the analyses of test data with examples. In addition, several projects which included non-static load testing are discussed INTRODUCTIONPile load testing complements the subsurface information and pile design by providing further data on pile-soil interaction for the selected pile type and installation method. Traditional approaches to pile load testing in New York City involve static load tests to verify the design capacity of the piles for a given minimum factor of safety.In the late 1950's, Dr. Phillip C. Rutledge summarized his views on the philosophy of pile foundations in an unpublished, in-house document. He viewed pile foundations as good illustrations of pertinent and impertinent aspects of geotechnical engineering. In the analyses of piles he divided engineering into four general types:(a) Theoretical engineering in which decisions are made based on theoretical analyses. This represents ideal engineering, in which all factors affecting the pile design are well established or, at least, few simplifying assumptions with known effects on the analyses are made."

Jan 1, 2005