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By Bruce Haldeman

Timber has been used as pile support for structures for 6,000 years. Some means of preservation of wood go back almost that far. Timber piles support all types of structures ? some are buried below the water table; others raise a home for protection from animals or a chief's home for prestige. Millions of wood piles have been driven for bridge support. Earlier piles were driven by hand then by ingeniously raised weights. Charring, animal fats and oils have been used for preservation. Coal tar creosote and other preservative methods started only in the early 1800's and give effective protection.

Jan 1, 1984

By James J. Cahill

Contractor's working in an urban environment face a multitude of working conditions. There is no typical "Downtown" job site. From afar we just see the skyline, or up close a specific building. This, of course, does not give us a clue as to the site conditions the foundation contractor faced in doing his work. The open, downtown building site is still available on some projects, but they are becoming rare as our cities are becoming more developed. A typical site today might include any one or several of the following problems: A. Deep pit with no ramp access B. Multi-type known or unknown obstructions C. Height limitations D. Load restrictions E. Existing adjacent building founded on shallow foundation F. Existing foundations G. Existing tunnels, utilities or subways

Jan 1, 1991

By J. Stacho, Frankovská. J.

"Abstract The use of continuous flight auger (CFA) piles in Slovakia has increased significantly in recent decades. High-rise building of administrative centre Lakeside Park in Bratislava is based on piled-raft foundation. The technology of CFA has been used due to the advantages of this technology in comparison with driven and bored piles in local geotechnical conditions. Piles have been designed in accordance with Eurocode 7. Resistance of piles was calculated by using an analytical calculation model for bored piles according to Slovak technical standard and CFA technology has been taken into account by coefficient equal to 1.1. Settlement of piles was calculated by using a calculation model which is being used in Czech Republic and Slovakia. Two well instrumented static load tests were carried out to verify the pile design. The results of static load tests showed that the design was conservative. The paper presents analysis of numerical modelling of CFA pile and static load tests. Load-settlement curves and load distribution curves over pile shafts are compared. Software Plaxis 2011 has been used for numerical modelling. Hardening soil model allows considering over consolidation of Tertiary Silts and water pressure in deep sandy lenses. The article also presents the parametric study where the influences of pile-soil interface reduction factor, over consolidation ratio and material models of soils are analysed. The results of numerical modelling showed that the most appropriate results have been obtained when the interface reduction factor equal 0.9 and real behaviour of groundwater were considered. The conclusion of the paper confirms that mechanical behaviour of the ground can be better understood and determined by using FEM than analytical methods.1. IntroductionPiles are among the most frequently used elements of deep foundations. Piles transfer loads down to a suitable bearing stratum when the soil immediately below a construction is unsuitable. Piles are also used to reduce settlement of structure. At present, the requirements of limit settlement of structures are more stringent. Examples of these structures are commercial and administrative centres that form a complex of different tall buildings. High-rise buildings cause greater contact stresses than connected low-rise buildings. Pile foundations in such cases should be placed under the high-rise buildings to achieve an appropriate settlement.Resistance of piles can be determined from static load test results, in-situ tests and empirical experiences or calculations. Static load tests give the most reliable results, but these tests are also the most expensive. This is the reason for constant development of computational methods. Especially numerical methods give more accurate results by using more sophisticated material models e. g. hardening soil or hypoplastic model."

Jan 1, 2014

By Darrell L. Beddard

Pile driving started October 29, 1993 and was completed on January 27, 1994. Field work included driving piling from ground surface at one site and at or near proposed footing elevations for the remainder. Piles were driven to specified tip elevations or the elevations directed by the Project Manager. In an attempt to address what installation technique(s) performed the best, several methods were used, including varied predrilled depths, open ended piles, closed ended piles, and the use of both impact and vibratory hammers. Piles were driven closed ended where possible to study the feasibility of this option to reduce construction costs associated with pile cleanout. Piles were driven to different depths to measure capacity variations. The 24-inch (610 mm) diameter piling were driven in one piece while the 42-inch (1.07 m) diameter piling was driven in two segments. A total of 79 piles were driven for the four sites, 74 of the 24-inch (610 mm) diameter and 5 of the 42-inch (1.07 m) diameter. Various hammers were used to determine which hammers provided viable solutions to the potential problems anticipated in the design phase. Hammer selection was based on the driveability studies. Equipment included a 175 ton (1.56 MN) crane, support crane for pile stabilization, crane mounted auger drill, offshore leads, Delmag D30-32, D46-32, and D62-22 diesel hammers, an HPSI 2005 single acting hydraulic hammer, a Foster IHC S-90 double acting hydraulic hammer and a Kencho VM2-25000AII vibratory hammer with the weights set to produce 17,500 pound-inch (1.98 kN-m) of eccentric moment.

Jan 1, 1996

By Robert E. Fosse

Driven 14-inch-square concrete piles were used as the foundations of Genentech Hall at the new University of California, San Francisco Mission Bay Campus. The five-story, steel eccentrically-braced frame building is currently under construction at a 43-acre property located in a former large shallow marshy inlet from San Francisco Bay. The piles were driven through 10 to 25 feet of fill and 20 to 60 feet of soft compressible Bay Mud into an underlying dense sand layer. Pile design capacities were developed for traditional allowable stress design, load factor and resistance design, and ultimate design criteria. The ultimate level capacities were for checks of loads occurring when the links in the eccentrically-braced frame yield during an earthquake. A load test program was performed to confirm pile design recommendations. Two test pile locations were selected for compression, tension, and lateral load tests to evaluate pile capacity and pile/soil stiffness under long-term, short-term and rapid loading conditions. Maximum test loads were 1000 kips downward, 350 kips uplift and 50 kips lateral. Foundation construction began by driving 34 indicator piles with a Delmag D46-32 diesel hammer of 113 foot-kips maximum rated energy. All indicator piles were monitored during initial driving using the Pile Driving Analyzer. Restrike data, obtained several days after initial driving, indicated significant pile-soil setup and typical pile capacity increases from 750 to 1000 kips. The majority of the 1242 production piles were then driven to acceptance criteria of 75 blows per foot and a minimum embedment of 10 feet into the dense sand bearing layer. Piles driven to full length without achieving the blowcount criteria were evaluated on a case-by-case basis. Acceptance of these piles was established by evaluating restrike data.

Jan 1, 2002

By B. B. Broms

A method for calculating the bending moment induced in misaligned or bent piles is described, The maximum bending moment varies with the angular rotation between the pile segments, the coefficient of horizontal subgrade reaction of the soil and the flexural rigidity of the piles. A case history involving damages to misaligned 365 x 365 mm square precast concrete piles is described.

Jan 1, 2010

By Karen C. Armfield, Gisele R. Passalacqua, Joanna Smith

When selecting a solution for improving resiliency at facilities, such as airports, utility and transit sites, there are many options to protect structures and equipment against potential flooding. Each case involves an evaluation of the several key factors such as: design flood parameters, the geography and geological conditions below the site, the facility, and the layout of buildings and equipment to be protected. Upon reviewing these conditions and conducting a cost analysis of various options, the most suitable approach to protecting a facility can be determined. This paper will compare the conditions at various New York City sites, and give detail to the solutions utilized at these sites to improve resiliency and protect each facility. Flood wall types varied as did the strategies for raising critical equipment, to meet the Federal Emergency Management Agency (FEMA) and American Society of Civil Engineers (ASCE) 7 guidelines. Due to granular soil conditions, some sites may experience soil seepage below the flood wall resulting in the need for underground cut off systems. The authors will also present detail regarding the solutions used to control seepage. Various cut off systems will be discussed such as grouting and sheeting, explaining the factors that may impact the choice of systems. Another consideration in flood resiliency is the potential for a buoyancy condition on basement slabs when localized flood barriers are employed on first floor doors and windows. The authors will discuss the potential impacts of this condition on facilities and methods to mitigate this issue. 1. INTRODUCTION New York City is an urban coastal Metropolis with varied geology and low land areas. This includes but is not limited to sandy soils at Coney Island and the John F. Kennedy Airport. Soft marshes are found near Flushing Queens and LaGuardia Airport. Heavy rains and coastal storms caused disruption to daily life and heavily affected the economy of this vibrant City. For instance, in lower Manhattan business was interrupted in the Financial District. Power outage was widespread; commuter trains and subways were stopped and put out of service. Additionally, numerous residential homes were damaged in Coastal Neighborhoods such as the Far Rockaways and Staten Island. 1.1. Superstorm Sandy Flood Statistics On October 29, 2012 Superstorm Sandy impacted numerous facilities in the New York City Metro area. The resulting damage cost New York City more than $42 billion in repair costs. $33 billion was allocated to repair housing and infrastructure, and $9 billion was allocated to protect transit systems1. One of the major issues that impacted the city in terms of its preparedness was the high flood surge. The surge surpassed the former base flood elevation and reached as high as 13.88 feet (above mean lower low water - MLLW) in Battery Park at 9:24pm that evening. Tottenville, Staten Island experienced more damage where the water was recorded at +16 (North America Vertical Datum of 1988 - NAVD88), which is equivalent to 18.7 feet above MLLW (see Fig. 1). Not only was the surge at record levels, the waves in New York Harbor were also at record level where some buoy stations recorded waves of up to 32.5 feet. The City released “A Stronger, More Resilient New York” in June 2013, a plan laid out to rebuild communities impacted by Sandy and improve the resiliency of the infrastructure and buildings in New York City. Figures below help to illustrate the extent of the inundation relative to the projects being discussed.

Jan 1, 2018

The intent of this manual is to provide guidelines for inspectors of drilled shaft construction otherwise referred to as drilled piers, caissons or bored piles. It should also be helpful to train beginning geotechnical engineers with limited first hand experience or for geotechnical engineers who are training inspectors. It is expected that the general guidelines and procedures described here will be supplemented by local geotechnical engineers working in a particular region based on local practice and experience. Since drilled shaft construction procedures vary widely based on local geology and size of project, an all-inclusive manual is not considered practical. This manual focuses on traditional topside inspection for routine drilled shaft construction. Other inspection and evaluation methods that rely on electronic equipment are available, but these methods require extensive training and experience in the interpretation of results. These more sophisticated methods of drilled shaft inspection and evaluation are common in construction, but they are usually provided by specialty subconsultants. The subconsultant will typically submit a report for each shaft, which will be reviewed by the geotechnical engineer. Other manuals are available to describe the electronic methods of drilled shaft inspection.

Jan 1, 2004

By John S. McCartney, Ismaail Ghaaowd

This study presents the results from centrifuge modeling experiments performed to understand the effects of temperature changes on the pullout capacity of scale-model energy piles embedded in normally- consolidated clay layers. The energy pile under investigation is an aluminum cylinder instrumented with internal strain gages and thermocouples, and its temperature is controlled using an internal electrical resistance heater. The energy pile was first heated until the temperature, pore water pressure, and volume change of the surrounding clay layer stabilized, after which the energy pile was cooled. Pullout tests were then performed on the energy piles heated to different temperatures to understand the effects of the preceding heating-cooling cycle on the pullout capacity. In addition, the clay undrained shear strength profiles were measured using push-pull T-bar penetration tests before and after heating. INTRODUCTION When a heat source such as an energy pile is embedded in a saturated clay layer, temperature changes will result in changes in pore water pressure as the rate of heating is typically faster than the rate of pore water drainage (Campanella & Mitchell 1968, Abuel-Naga et al. 2007, and Ghaaowd et al. 2016). Although all soils will initially expand during undrained heating, normally consolidated soils typically exhibit permanent contraction while overconsolidated soils exhibit expansion after sustained heating when drainage is allowed (Vega & McCartney 2015). Subsequent drained cooling typically leads to elastic contraction. Thermally- induced changes in pore water pressure and volume during transient heating and cooling may affect the soil- structure interaction of energy piles, as well as the ultimate capacity of the energy pile. This study is relevant as relatively few studies have been performed on the behavior of energy piles in soft clay (e.g., Ng et al. 2014), with most focused on the behavior of drilled shaft energy piles in stiff rock or overconsolidated clays (e.g., Laloui et al. 2006; Murphy et al. 2015; Wang et al. 2015; McCartney and Murphy 2017).

Jan 1, 2018

By Roderic A. Ellman

The new Woodrow Wilson Bridge (WWB) will replace the existing bridge over the Potomac River to connect Alexandria, Virginia to Prince Georges County, Maryland. The new WWB will extend approximately 1.1 miles across the river, with a 367-ft long bascule span in the main river channel where the water depth is about 36 ft. The subsurface soil profile consists of up to 50 ft of a soft organic silty clay layer that is very vulnerable to scour, underlain by a deep deposit of hard sandy clay. Foundation construction in the Potomac River required the use of cofferdams to allow structural concrete work to be performed in the dry. This paper will the present the types of cofferdams used to construct the foundations for the WWB replacement project. The bridge is primarily comprised of fixed spans in relatively shallow water and a bascule span over a navigation channel in relatively deep water. Foundation construction included the installation of 48? to 72? open end steel pipe piles and cast-in-place concrete pile caps. To achieve the desired bridge appearance, pile caps were required to extend below the water surface and below the existing river bottom in shallow water locations. Conventional steel sheet pile cofferdams with tremie concrete seal were used to construct fixed span, shallow water piers. Selection of deep water bascule span foundation cofferdams was governed by several factors including contraction scour, environmental considerations and cost. Potomac River cofferdams, i.e., relatively shallow depth cofferdams that are supported by the foundation piling were selected. This cofferdam system provided a shallow profile which minimized contraction scour and the amount of filling in the river. Design issues include load selection and cofferdam stability in very soft alluvial soils. Construction issues include erection sequence, tremie concrete mix design and placement procedures.

Jan 1, 2013

By Larry Rayburn

In the spring of 1999, construction commenced on the new Steelers Football Stadium in downtown Pittsburgh, Pennsylvania. Richard Goettle, Inc. (RGI) was the successful bidder to install the specified augercast piles for the foundation package. Description - Pittsburgh Steelers Stadium The new stadium will house the Pittsburgh Steelers Professional Football Team. It is widely believed that if a team is provided with a modern playing facility, that a winning season will ensue (Not always the case). The new stadium location is on the north side of Pittsburgh on the Ohio River, and just downstream of the confluence of the Monongahela and Allegheny Rivers. The site is west of existing Three Rivers Stadium. The Three Rivers Stadium was built during the late sixties and housed both the Pirates Baseball and Steelers Football Teams. The Public Auditorium Authority elected to replace this outdated stadium with two new stadiums, one for each professional team. The landmark stadium was imploded in February of 2001.

Jan 1, 2001

By Jorj O. Osterberg

Until ten years ago, the largest load tests on drilled shafts (bored piles) were about 3,000 tons (27MN). These tests were made with kentledge (large weights, usually concrete blocks) stacked up as a reaction to the applied downward load of a hydraulic jack. In some cases, the jack load is resisted by a load frame held down by piles or anchors connected to the frame. When the test loads exceed 3,000 tons (27MN), these methods become cumbersome expensive and time consuming. The Osterberg (O-cell) test method does not require any reaction load. It has become the only cost effective method for static load testing of high capacity shafts. Over 650 load tests have been performed with this method, 86 of which were over 3,000 tons (27 MN) and 40 over 5,000 tons (44 MN), and the largest test load was 17,000 tons (150 MN). Tests have been made on sands below the water table, shafts ending in rock sockets, and cemented sands and gravels. Test results and details for selected load tests are discussed.

Jan 1, 2002

By Gregory J. Canivan

Three test pile programs were conducted in Charleston, South Carolina to evaluate differences in bearing resistance due to installation methods. The tested piles were installed with impact hammers and vibratory drivers through soft clays and/or loose sands into the Cooper Marl, a stiff calcareous marine clay or silt. Piles driven into the Cooper Marl experience significant capacity gain with time following initial installation due largely to pore pressure dissipation. Pile size and pile type were both known to affect pore pressure generation during installation and subsequently the capacity gain with time. The test programs were primarily conducted to optimize pile design values and construction methods with regard to trestle construction but the results also contribute to the understanding of driven pile behavior. High strain dynamic testing was performed on several open-end pipe and H-piles. The measured difference in long-term bearing capacity of the H-piles as a result of the two installation methods was negligible, while the short-term bearing capacity of the pipe pile was larger when the piles were installed using impact hammers. The lower short-term resistance in the vibratory driven piles is attributed to larger excess pore pressures generated during installation compared to those generated during impact driving.

Jan 1, 2002

By Thomas Passlick

By means of further developed machines and techniques and with growing experiences in jet grouting, the challenge of this building method becomes more and more complex. To keep the concerning risks as low as possible, the requirements on the quality assurance continuously in­crease. The construction of a 37.0m deep seated slab for the Amsterdam metro station Vijzelgracht in marine clay represents such a complex task. This paper summarises the required measures of quality assurance. In particular a new hydraulic measuring device is introduced with which it was possible to detect the column diameter of 2.6m at a depth of 37.0m during the production process and with a very high accuracy.

Jan 1, 2006

By Robert B. Bittner

The Sutong Bridge across the lower Yangtze River in China will have, when completed, the longest span (1,088 m) and the highest towers (306 m) of any cable stayed span in the world. The foundations for this record setting span will also be record setting. They are located in water depths exceeding 30 m with maximum flows exceeding 3 m/sec. The soil at the site of the main pylons consists of layers of silty sands and silty clays extending to bed rock at 270 m below river elevation. This paper describes the innovative methods used by the team of foundation designers and constructors to support this record setting bridge at this very challenging site. This paper covers three specific topics related to the foundations of the Sutong Bridge: ? Design and construction of the 131 drilled shaft (2.8/2.5 m diameter and 114/117 m long) under each of the two main pylons, ? Design and construction of the scour protection for the two main pylons, ? Construction methods used to construct the waterline pile caps (113.8 m by 48.1 m by 13.3 m deep) under each pylon.

Jan 1, 2005

By F. W. Liang

The geology of pearl River estuary belongs in strong weathered rock quaternary geological systen, so the conditions are complication. Since 80's we built the first deepwater wharf of Shenzhen chiwan port which has 3 berths of 10000 dwt, We have built 3 berths for vessels of 40000 dwt both in Shekou Port and Chiwan port. The berths for carriers of 10000 dwt in Yantian Port of Dapeng Bay are constructing now. In the five years, We built more than 20 deepwater berths of 5000 dwt to 40000 dwt. This paper will introduce how to solve the difficulties of the complex geological conditions and how to use the new fashion construction. We will reduce the period of engineering construction and get good quality and make a good beginning of rapid development of port construction in ShenZhen Special Economic Zone.

Jan 1, 1991

By Dominique Vié

Standards methods covers the procedures for testing deep foundation to determine the force and velocity response to an impact of a pile driving hammer or similar device. The results of analysis generally include an assessment of pile integrity and the value of maximum dynamic stresses. But evaluation of static bearing capacity remains a matter of individual engineering judgment. A new 1D finite elements model has been developed for dynamic stresses and velocity analysis. Following an international benchmark of bearing capacity prediction organised by the Belgium Building Research Institute (BBRI), 12 piles in a site of fissured stiff tertiary clay tested in 1999, and 12 piles in a site of dense sand tested in 2001, comparison are proposed between analysis of dynamic tests and static tests results. A procedure is proposed to take in account the results of dynamic test for evaluation of bearing capacity.

Jan 1, 2002

By Francis J. Arland

The installation of augered cast-in-place (ACIP) piles requires careful quality control to assure a successful pile installation. Unlike steel, pre-stressed concrete or other types of driven piles, which are shop fabricated, delivered to the site and typically driven to a minimum tip resistance, augered cast-in-place piles are installed to a pre-determined tip elevation or to a refusal criteria. The structural section of the ACIP pile is constructed during pile installation and cannot be inspected prior to installation. Therefore, a carefully administered quality control program is essential to a pile foundation that will meet or exceed design requirements. This requires an experienced team consisting of the Geotechnical Engineer, Contractor and Inspector. The focus of this paper is to discuss the responsibilities and duties of the ACIP piling Inspector. Qualifications of the Inspector The qualifications of the inspector are related to the complexity and difficulty of the proposed project. Ideally, the Inspector should be an individual with a degree in civil engineering with special emphasis in geotechnical engineering. A properly trained technician with geotechnical engineering experience working under the direct supervision of a geotechnical engineer may be able to provide competent inspection on some projects. It is important that the Inspector have a good understanding of subsurface and ground water conditions and how they will affect pile installation. The Inspector must understand ACIP pile installation procedures and be able to communicate with the Contractor, Structural and Geotechnical Engineers; and maintain a detailed pile record for each installed pile.

Jan 1, 1997

By Chris Harnan

This paper describes the geology of three European cities and outlines how the geology has lead to the development of specific foundation construction techniques. Comparative tables of techniques commonly employed are given in Section 5. It can be seen that despite the presence of the 'single market', techniques still have wide diversity despite some similarities in geotechnical conditions.

Jan 1, 2000

By Paul M. C. B. M. Cools, Martin Th. van Staveren

In 2010, the 5-years joint industry programme Geo-Impuls started in the Netherlands. The ambitious goal of this programme is to reduce geotechnical failures in our civil engineering projects by half in 2015. In the Geo-Impuls programme over 40 client organizations, engineering firms, contractors, research institutes, and universities are involved. In a risk-driven way, and based on top risks and dilemmas, the participants defined three central development themes. These themes are (1) contracts, for dealing with legal issues, (2) geo-engineering, for dealing with technical issues, and (3) communication, for paying attention to differences in risk perception by the human factor. In total 12 Working Groups contribute to these themes by producing one or more specific tools. These provide practical solutions for how to deal with contractual, geotechnical, and communication issues. The tools include working processes, guidelines, best practices, as well as some instruments. The development of these tools, as well as the available results, will be presented in this paper. From the start, Geo-Impuls embraced geotechnical risk management (GeoRM) as the risk-driven way of working for geotechnical engineering and construction. Over the past years, GeoRM and its supporting tools were already successfully applied in several projects. Therefore, the paper also describes also the GeoRM implementation process, including the quality assurance and control. Finally, the effectiveness of GeoRM will be discussed, by summarizing an analysis of all published geotechnical failures and accidents in construction projects in the Netherlands, which decreased substantially over the past 4 years.

Jan 1, 2017