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By Terrence R. Udland, Russell D. Call

"Honored with a DFI 2006 Special Recognition Award, the Four Bears Bridge was constructed across Lake Sakakawea and opened to traffi c in September 2005. The very large lake size and severe winter conditions required an effi cient foundation design capable of resisting extreme ice loading and able to be effi ciently constructed in waters up to 90' deep (27.4m).DESIGNING FOR EFFICIENCYLocated in a remote area of North Dakota, the Four Bears Bridge replacement was a major undertaking for the North Dakota Department of Transportation, with dual goals of providing a new structure that would endure a severe environment, while enhancing the natural beauty of the area. Competing bids would achieve the best price for the owner, challenging the design team to creatively solve the engineering challenges unique to the site. Foundations for North Dakota’s new Four Bears Bridge had to accommodate water level fl uctuations of up to 40 feet (12m), along with extreme ice loading and be effi cient in order to be the low cost solution at the time of bidding. All three major criteria were achieved through the use of an effi cient ‘fl oating’ lost precast concrete cofferdam founded on steel pipe piles, which allowed the contractor to achieve the project schedule. The result is an award-winning bridge that is contextually sensitive to the environment. The bridge aesthetics pay tribute to the Three Affi liated Tribes, the Mandan, Arikara and Hidatsa, who reside on the Fort Berthold Indian Reservation, adjacent to the bridge site.The original Four Bears Bridge was located over the Missouri River near Elbowoods, the native grounds of the Three Affi liated Tribes. Construction of the Garrison Dam in the early 1950’s created Lake Sakakawea, a fl ood control project on the Missouri River, and resulted in the area being fl ooded. The bridge, along with many tribal members, was relocated to a site near New Town. The bridge provides the primary crossing of Lake Sakakawea and is a critically important transportation element for the residents of the Fort Berthold Indian Reservation. The relocated bridge had become functionally obsolete and not replacing it would require a detour of 170 miles (274km). The North Dakota Department of Transportation determined that it should be replaced. In order to achieve the most effective solution, the North Dakota Department of Transportation selected a design team responsible for the creation of competing steel and concrete designs that were competitively bid. The design team was led by Kadrmas Lee & Jackson, with FIGG responsible for the concrete bridge design, while Lichtenstein Consulting and Kadrmas Lee & Jackson completed the alternate steel bridge design."

Jan 1, 2007

By Edward Jacobsen, Patrick J. Lydon

"The ongoing expansion of the Oak Creek Power Plant in Oak Creek, Wisc., includes a tunnel bored in rock that connects to four vertical intake shafts approximately 1.5 miles (2.4 km) offshore in Lake Michigan. In 2004, Case Foundation Company was awarded a lump sum contract to install these intake shafts. In spite of delays that shortened the May to September construction season by up to 50%, four shafts and liner assemblies were drilled in 2005 and 2006. The shafts were connected to the tunnel in 2007 by mining upward to reach the lower portion of each liner and then removing its internal bulkheads so that lake water fl owed into the tunnel. The project is one of the largest private construction projects ever undertaken in Wisconsin. The expansion adds 1,230 megawatts of generation. In addition to the tunnel and offshore work, there will be 16 miles (26 km) of railroad track and 6 million cubic yards (4,600,000 m3) of earth work. The 27 ft (8.2 m) diameter tunnel, drilled some 150 ft (46 m) below the surface of Lake Michigan, originates onshore at a pump house. A structural slurry wall was constructed as the foundation for the pump house. The tunnel passes to the south near the current water intake before bearing east toward the new offshore intake shafts, which are 12 ft (3.6 m) diameter by 108 ft (33 m) long steel liner assemblies. These were grouted in place from approximately 3 ft (1 m) above the crown of the intake tunnel and then to 20 ft (6 m) below the lake bottom.Site GeologyOffshore. The plant site is north of the Racine-Milwaukee county line in an area affected by glacial activity. The soil conditions encountered at each shaft location were consistent, with noticeable variations occurring in the top of rock elevations that sloped downward from the innermost to the outermost shaft."

Jan 1, 2008

By Gisele R. Passalacqua, Taylor Malangone, Subhash Mahali

New York City is a busy metropolis with 8 million people. New York has the largest public transportation system with 6 million riders a day throughout the subway system. Keeping this infrastructure in service is vital to the overall economy of the region. Hurricane Sandy proved to have a devastating impact on infrastructure in Metropolitan New York. New York City Transit is on the forefront to provide resiliency and maintain its facilities with the use of flood protection systems. This paper presents flood protection structures utilized at Hammels Wye substation site in Far Rockaway, Queens, New York. The site is in close proximity and surrounded by water. The subsurface conditions consist of loose silts overlain by medium dense glacial sand. The high groundwater level combined with limited access to the site presented challenges. A flood protection system consisting of flood walls was recommended for this site. In certain areas the flood walls consisted of retaining walls supported on micropiles. For other areas, the flood walls consisted of steel sheet piles with jet grout columns to reduce seepage below the walls. The effect of driving sheet piles with vibratory hammers on nearby existing structures is always a concern. Recently, hydraulic hammers with variable moment/frequency are being considered as a mean to reduce vibration effects during driving. In this project, an instrumentation testing program was performed to measure peak particle velocity during sheet pile driving utilizing the variable moment vibratory hammer. Plots of peak particle velocity versus frequency were generated. This paper will present the design aspects of the flood walls and construction challenges during installation. This will prove beneficial to engineers in both design and construction fields.

Sep 8, 2021

By Magued G. Iskander

The deterioration of concrete, steel, and timber is a serious hindrance to construction in marine and corrosive environments. Composite materials such as fiber-reinforced polymers (FRP) can offer performance advantages for construction in these environments. In the last decade, piling made of FRP composites has been used experimentally throughout North America. However, composites face obstacles because they do not have a long track-record of use in civil engineering structures. A comprehensive review of the current experience in research, testing, design, and practice of composite piling is presented in this paper.

Jan 1, 2002

By James Green

It has often been said that the best contracts written are by people who are suspicious of each other. The Spanish philosopher, Ortega y Gasset, said: "Every contract is an Act of Distrust." The arena for dispute settlement outside of the courts is increasing day by day - contracts, especially construction and civil engineering contracts, are written containing arbitration clauses for settling disputes - the very drafting of standard forms of contract, do in some instances by their very construction, create an ambiguity as to intent and provide a breeding ground for dispute. I come from a land far across the sea - the most southern land before the South Pole. Being a young country, 150 years old, we are still progressing - being far removed from the trouble free zones of the world and nuclear free we enjoy a lifestyle second to none.

Jan 1, 1987

By W. J. Grose

The Embankment Place office development over the platforms of Charing Cross Railway Station in London has presented many interesting and unusual problems to the engineers involved with the project. The main structure is supported on widely-spaced columns which penetrate the station platforms and underlying vaults, calling for high capacity foundations built in severely restricted spaces. Hand-dug underreamed piles were chosen. Whilst a conventional design approach was taken to size the piles, a detailed appraisal of ground movements was made to explore the effects of the new building loads on the existing foundations, not only beyond the site perimeter but also those amongst the new foundations. Before construction of the pile proper could take place, it was necessary to sink a caisson through the upper unstable and water-bearing soils. This being identified as a high-risk item, a full-scale trial was carried out prior to embarking on the main works. The twenty-one hand-dug piles were 2.5m diameter, over 30m deep and belled out to between 4.5m and 6.6m.

Jan 1, 1989

This work shall consist of furnishing and driving foundation piles of the type and dimensions designated on the plans or in the special provisions including cutting off or building up foundation piles when required. This specification also covers providing test piles and performing loading tests. Piling shall conform to and be installed in accordance with these specifications, and at the location, and to the elevation, penetration and bearing capacity shown on the plans or as directed by the Engineer. Except when test piles are required, the Contractor shall furnish the piles in accordance with the dimensions shown on the plans or special provisions. When test piles are required, the pile lengths shown on the plans are for estimating purposes only and the actual lengths to be furnished for production piles will be determined by the Engineer after the test piles have been driven. The lengths given in the Engineer's order list will include only the lengths anticipated for use in the completed structure. The Contractor shall, with-out added compensation, increase the lengths shown or ordered to provide for fresh heading and for such additional length as may be necessary to suit his method of operation.

Jan 1, 1989

By Kirk Ellison, Sherif Elfass, Ramin Motamed, Kevin V. Stanton

"The determination of accurate load transfer curves are essential for estimating deep foundation loadsettlement response using t-z style analyses. While recently developed semi-empirical methods from Ashour et al. (2010) and Ashour & Helal (2012) have shown promise in preliminary studies, they have not yet been thoroughly benchmarked against a more widely accepted approach. To address this issue, these recent procedures are implemented in the computer program CGI-DFSAP to predict the results of four Osterberg-cell (O-Cell) load tests. These predictions are compared to outcomes obtained following the recommendations from Reese & O’Neill (1988) for t-z analyses of drilled shafts in sand and clay which are carried out with the program TZ-PILE. Overall, the results suggest that the new approach offers improved accuracy regarding predictions of drilled shaft response to axial loading.INTRODUCTIONThe behavior of axially loaded deep foundations is often analyzed using a technique known as the t-z method. In this method, deep foundation elements are broken into multiple segments which are supported by discrete nonlinear springs to capture the contribution of both side-friction (t-z springs) and end-bearing (Q-z springs). Hence, the t-z and Q-z relationships dictate the predicted load-settlement response. A number of different approaches have been developed to estimate load-transfer curves with some relying solely on empirical data from laboratory and field experiments (i.e. Coyle & Reese, 1966; Vijayvergiya, 1977) and others based mainly on analytical frameworks (i.e. Kraft et al., 1981; Randolph, 1994). Reese & O’Neill (1988) provide recommendations which are widely used for developing t-z and Q-z curves for analyzing drilled shafts. This method is hereafter referred to as Method 1 (M1). It should be noted that these empirically derived relationships are only applicable for problems associated with drilled shafts and are therefore not appropriate for developing load-transfer curves for other types of deep foundations (i.e. driven piles). This is because of the difference in the frictional resistance which can be developed between a circular concrete-soil interface as opposed to that of other materials (i.e. steel) and/or different cross sectional geometries.The M1 load-transfer curves form the basis for the t-z analysis of drilled shafts implemented in the computer program TZ-PILE (Ensoft, 2014). In light of this, TZ-PILE is employed herein as a reference to compare against the capabilities of another method of implementing t-z style analyses. This method is based on a semi-empirical framework for soil behavior developed by Norris (1986) and is implemented using the program CGI-DFSAP (Computers & GeoEngineering Inc., 2011). More information concerning this approach, hereafter referred to as Method 2 (M2), is given in subsequent sections."

Jan 1, 2017

By Emilie Lapointe, Fernando Famania

"A reliable determination of the in-placed cement factor, as defined by mass of cement over volume of final element of treated soil, allows the optimization of cement usage to achieve treated soil requirements. Cement determination tests were performed on soil-cement samples, both fresh (as per ASTM D5982) and hardened (as per ASTM C1084). This paper reviews the calibration work required for the D5982 determination of cement content by the heat of hydration method used on soil-cement samples obtained by wet-grabbing. Using the correlation curves in the field provides a rapid assessment of cement content hence optimizing the cement injection rate to match laboratory tests previously conducted. Cement determination tests on hardened soil-cement specimens from wet-grabs and cores were performed using the oxides method. Samples, both cored and wet-grabbed, were tested in a given cement-treated element, and in different soils to inform on the expected variation in cement content from field installation. Results indicate that both cement determination methods are valid for forensically determining cement contents and that they provide better assessment than the conventional field reporting methods. The methods can be used to optimise the cement usage as well as for Quality Assurance, especially when coring quality is poor.INTRODUCTIONThe degree of improvement, and inherent strength, which is attained in a deep-mixed soil is a function of many factors. The binder type, the existing soil, the mixing conditions and the curing conditions are the categories of factors influencing the strength of a given cement-treated soil as agreed by the deep mixing community and as summarized by the Coastal Development of Technology [CDIT] (2012). Given a site with existing soils and conditions requiring soil improvement using a given binder, the designer and/or contractor can control the mixing conditions. Mixing conditions are inclusive of the degree of mixing, mixing duration and the quantity of binder. Once a deep mixing method has been chosen to mix optimally the in-situ soil, the quantity of binder is the only remaining factor to be optimized. The quantity of binder, in the construction industry is commonly referred to as the field binder factor [ar] and defined by the mass of binder over the volume of soil treated with kg/m3 as unit. In research, the quantity of binder is referred to as the binder content [Cc] and expressed as a ratio of the mass of binder over the mass of dry soil mixed."

Jan 1, 2015

By Joseph T. Coe, Siavash Mahvelati, Philip Asabere

Characterization of existing foundations remains an important issue as foundation reuse and rehabilitation continue to garner increased attention. In the case of unknown foundations, geophysical and nondestructive testing (NDT) methods have been utilized in the past to evaluate foundation geometry and could serve as useful tools in the case of foundation reuse. A comprehensive study was initiated in the late 1990’s and early 2000’s that evaluated the effectiveness of the available geophysical and NDT technologies to characterize unknown foundations for scour evaluation purposes. At the time of that study, the Multichannel Analysis of Surface Waves (MASW) geophysical method was in its infancy and not widely used. Since then, MASW has become increasingly prevalent in geotechnical applications as the method presents a number of potential advantages when characterizing the subsurface, including rapid testing, increased signal to noise ratio, and ability to resolve velocity inversions. This paper presents a case study that explores the abilities of MASW as an unknown foundation characterization tool. MASW was applied to determine subsurface stiffness at a bridge foundation site in the Philadelphia metropolitan area. One MASW survey line was performed immediately over the foundation of interest and another was performed over a control zone adjacent to the foundation to establish a baseline site profile. The purpose of this testing was to examine whether MASW could establish the geometry of the foundation at this site. This paper presents the site conditions and MASW testing procedures, followed by a discussion of data analysis and interpretation.

Jan 1, 2016

By Sam Warren, Antonio Marinucci, Genesis Z. Figueroa, Anne Lemnitzer

Drilled Displacement Piles (DDP) provide an ideal deep foundation solution that combines the benefits of ground improvement with traditional advantages of piling systems. This paper consolidates data from 20 construction projects in which more than 30 DDPs were installed and tested axially. High quality site exploration data (e.g., Cone Penetration Test and Standard Penetration Test) were evaluated to derive geotechnical analysis parameters. The test sites consisted of mostly mixed soil types with strongly stratified layers of sand, silt, and clay. Pile diameters ranged between 40 cm and 61 cm. Test results were compared with predictive methods developed specifically for DDPs as well as methods used in general geotechnical practice. The accuracy of the empirical methods is presented in terms of total pile capacity, pile length/diameter, and soil type. The large majority of all examined methods underpredict the in-situ pile capacities. It was also found that the difference between the tested and predicted capacity is strongly related to the level of improvement in the surrounding soil due to the piles’ installation. A general comparison between predictive axial accuracy and the observed level of ground improvement upon installation is also discussed.

May 1, 2022

By Giovanni A. Bonita

The United States Capitol Visitor Center (USCVC) is one of the largest underground structures ever constructed in the Washington, DC, metropolitan area. The 600,000 ft2 (55,750 m2) structure is entirely underground and immediately adjacent to the shallow foundations of the existing U.S. Capitol building. Interior building columns for the USCVC were supported on 186 drilled shafts that varied in diameter from 4 to 9 ft (1.2 to 2.9 m) and in length from 15 to 45 ft (4.6 to 13.7 m). The vast majority of the building utilities were located beneath the basement floor slab. It was decided at the onset of the project to proceed with construction prior to completion of the design drawings, and coordination between the underslab utilities and the drilled shafts had not yet been finalized at the onset of drilled shaft installation. Given depth and location restrictions of the outlets, relocation of the bulk of the utilities was not possible. Almost half of the drilled shafts were affected, leaving redesign as the most feasible remedial solution. The redesign involved adjustments to the shaft length, diameter, and bell. It took place on a case-by-case basis, sometimes only minutes before installation began. Coordination between the field and design team was excellent, and delay associated with the redesign efforts was minimal. In addition, the detailed, high-quality field records kept by both the contractor and field engineers allowed for accurate and fair estimations of the added drilled footage and concrete volumes placed. The additional service fee, which was minimal, was settled quick and fair.

Jan 1, 2006

By Mohammed Y. Fattah, Wissam H. S. Al-Sudani

"During installation of pile, a soil column is formed inside the pile. For small depths, the height of the soil column typically equals to the penetration depth (full coring state). As the penetration depth increases, the developed internal shear stresses become larger and reduce the amount of soil to penetrate. At the same time, the soil in pile at the bottom is compacted. This will continue until at a given moment, the soil column is a soil plug, and does not stop moving relative to the pile. This is because the shear stresses developed in the interior of the pile are greater than the load-bearing capacity of the ground.This paper presents the results obtained from 40 model pile tests carried out to assess the effect of soil plug on the model pile capacity. The piles are embedded in sand of different densities with different lengths of piles and types of pile-ends. The model tests are divided into two parts according to the type of end of the pipe pile used in the model pile test. The first part consists of 32 model open-ended piles with different lengths of soil plug inside the pile. The second part consists of 8 model closed-ended piles.It was concluded that open-ended pipe piles behave as a closed-ended if the soil plug formed inside piles in state partial plug or full plug. Length of soil plug depends on the type of installation and relative density. The pile load carrying capacity in dense sand is several times greater than those in medium sands especially in cases of closed ended piles or open-ended since the pipe pile can produce external and internal skin friction in addition to end bearing resistance that makes the total pile capacity close to that of closed-ended pile. Whether open-ended piles are driven or pressed in the fully coring - fully unplugged mode or in the partially plugged mode, the plug does contribute to static pile base capacity."

Jan 1, 2014

By K. Rambha Devi

The paper is an attempt to co-relate the findings of pile capacity using a number of formula suggested by various authors with the actual field load test results. Five locations consisting of wholly sandy or clayey soils were selected for this purpose. The clayey soils are on a hilly area having clays of medium to stiff consistency upto a depth of 20 m The sandy soils are near the bank of a river having angle of internal friction 'Ø' value ranging from 30 to 35 Degree. The details of the soil properties are given in Table-1 Bored cast-in-situ piles of 30 cm diameter and a length varies from 6.5 m to 13 m were designed and cast for load test to be carried out. The load applied was twice the design load. The load vs settlement curves were obtained. The theoritical values obtained by formula suggested by various authors were superimposed on the curves. From the careful study of these curves it is seen that De Ruiter and Berigen values are close to the actual results for clayey soil. For sandy soil it is found that both the BIS method and Meyerhof method found to give conservative resuslts. A multiplication factor is suggested to theoritical values for obtaining satisfactory results.

Jan 1, 1996

By Koichi Kobayashi

Performance-based approach to design of structures including foundations was adopted after enforcement of the revised Building Standard Law in Japan in 2000. The use of piled-raft foundation is favorable for medium-rise buildings in soft ground because of its good performance. In the design of the piled-raft foundation (Architectural Institute of JAPAN2002), vertical load is usually carried by the raft foundation, while the pile is primarily meant to control settlement of the structure. Shaft friction is expected to be larger in a nodular pile(Karkee, et.al., 1998) since it has larger surface area than a straight pile, and such piles are frequently used in piled-raft foundations. Since few structures with piled-raft foundation exist currently, the settlement characteristics of piled-raft foundation have not been fully clarified. To design piled-raft foundations with better confidence, the mechanism of vertical bearing capacity and the spatial distribution of settlement should be clarified, for which the actual behavior of the building-foundation system needs to be evaluated. This paper presents observations of settlement of a building with a piled-raft foundation at a soft ground site. The building is a steel structure covering an area an 766 m2, and consists of two-storey office block and one-storey warehouse block. The filled ground of about 5-m thickness at the ground surface is underlain by approximately 4-m thick alluvial sand layer below which lies about a 17-m thick alluvial clay layer with SPT N-value less than 2. The piles used in the piled-raft foundation are 12-m long nodular piles with nodal diameter of 500 mm (pile shaft diameter is 400 mm). The bored pre-cast piling method (Karkee, et.al., 1998) was used to install the piles. To evaluate the foundation settlement, the method of analysis of three-dimensional frame system, utilized widely in Japan, was adopted in combination with the foundation system. Basic assumptions were: (i) total ground settlement is evaluated as the sum of immediate settlement and consolidation settlement, (ii) immediate settlement is evaluated from the Mindlin?s solution in which strain dependency of shear modulus of soil is considered, (iii) settlement in clayey layers is evaluated by the one-dimensional consolidation theory, and (iv) shear spring between soil and pile shaft is represented by a hyperbolic function. The applicability of the method of analysis was verified by comparison with results of field monitoring of building settlement.

Jan 1, 2006

By Dimitris Pachakis

In this paper, the authors give a brief overview of the current practice guidelines and tools for the seismic design of sheet pile quay walls, emphasizing how the design guidelines are lacking when the existing structure performance evaluation is required to meet performance-based criteria. Relying on recent experience they explain how the existing practices can be amended to focus more on performance evaluation as opposed to design. An example is given of an old sheet pile quay wall analyzed and evaluated for its performance according the recent performance criteria devised for Californian Marine Oil Terminals.

Jan 1, 2011

By Michael A. Knott

Large lateral forces on bridge foundations due to extreme events such as vessel collisions, earthquakes, and wave forces on storm surges during hurricane events are often the controlling design condition for bridge foundations. A review of the American Association of State Highway and Transportation Officials (AASHTO) vessel collision analysis and design codes used in the United States for highway bridges will be presented. The paper includes the background and development of the AASHTO Guide Specification and Commentary for Vessel Collision Design of Highway Bridges (1991) and vessel collision provisions of the AASHTO LRFD Bridge Design Specifications (3rd Edition 2004 and the approved 2005 Interims). Experience in using the AASHTO codes will be discussed and observations on the adequacy and gaps, comparison with the European Standard Code, and recommendations for immediate and long term needs will be presented.

Jan 1, 2013

By Seung-hoon Lee

The use of piled raft foundations has been considered as an economical alternative to conventional piled foundations because a portion of the applied load is carried by the raft in the design of piled raft foundation. In analyzing the behavior of a piled raft foundation as a settlement reducer, an accurate estimate of settlements of the system should be made on the basis of the understanding of nonlinear behavior of piles in layered soils as well as the interaction between the raft, soils, and piles. Although the 3-dimensional finite element method and simplified analysis methods have been used for the design of piled raft foundations, these methods were found to be inadequate for the practical purpose or could not consider the interactions properly. This study developed an approximate hybrid method of analysis to be used for the practical design of piled raft foundations considering pile-soil, raft-soil, pile-soil-pile and raft-soil-pile interactions. In the presented method of analysis, the settlements of the system are estimated satisfying the compatibility of two separate models which are the flexible raft model consisting of 2-dimensional finite elements supported by springs representing soils and piles, and the group-pile model embedded in layers of soil having different properties. Comparisons with other analytical methods as well as a 3-dimensional FEM program were made to verify the sufficient capabilities of the proposed hybrid model for application to practical design and analysis of piled raft foundations.

Jan 1, 2008

By Reza Y. Khaksar

Presented is a rigorous solution for the three-dimensional stability analysis of vertical shafts (excavations) subjected to the self-weight of the soil based on the upper-bound theorem of limit analysis approach. A rigid-block translational collapse mechanism is assumed, with energy dissipation taking place along planar velocity discontinuities. This mechanism is optimized to obtain the critical failure mechanism giving the lowest factor of safety for stability of shafts. Based on comparisons with other solutions, the method is generally found to be accurate in predicting the stability of vertical cuts.

Jan 1, 2006

By Osamu Taki

The innovative Soil-Cement Mixed Wall Technique emerged in Japan and obtained recognition in the engineering and construction communities in the 1980's. This technique was introduced to the United States in 1986. It was accepted as the most credible construction technique by the U.S. Bureau of Reclamation for ground stabilization and cutoff wall work in the Jackson Lake Dam Project, Wyoming in 1987 and 1988. It was also accepted as a remediation technique by U.S. EPA for a Superfund Innovative Technology Evaluation (SITE) demonstration on in-situ solidification/ stabilization. The Soil-Cement Mixed Wall Technique consists of mixing in-place soils with cement grout or other reagent slurries using multiple axis augers and mixing paddles to construct overlapped soil-cement columns. The overlapped column panel is then extended to form an underground continuous soil-cement wall for use as a cutoff wall or a structural diaphragm wall for groundwater control and excavation support. By arranging the column panels in various configurations, the technique becomes a versatile tool for stabilization of soft or liquefiable soils.

Jan 1, 1990