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By J. Wennerstrand

Slender steel piles have found an increased use in Sweden in resent years. These piles are often driven throw soft normally consolidated clay to refusal in till or at the rock surface. In contrast to most other piles the bearing capacity with regard to failure of the shaft is in many cases smaller than the bearing capacity with regard to failure of the soil or rock at the lower end of the pile. Imperfections such as deviations from a straight line of the pile centerline and residual stresses in rolled and welded profiles are important for the capacity of the pile shaft. Even thow the second order moment caused by initial deviations in piles is only half of that in a column with the same slenderness, imperfections can and should be accounted for in much the same way as for columns.

Jan 1, 1989

By Kenneth Gavin

The accurate prediction of the shaft capacity of drives piles in sand continues to present problems for foundation designers. Research in this field has been carried out for many years and has yielded a wide range of design approaches -some of which have been shown by recent experimental work to be based on questionable assumptions. This Paper reviews some of the current popular design methods for piles in sand in the context of recent information obtained from high quality field tests conducted by institutions such as Imperial College London. A database of driven piles in cohesionless soils has been compiled from well documented (and reliable) case histories that have been reported in the literature. The measured shaft capacities of the piles in this database are compared with predictions made by the various methods and an assessment is made of the predictive performance and reliability of each method

Jan 1, 1996

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 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

By Masanoub R. Fujioka

A brief discussion of the methodologies involved in dewatering practices, particularly as used in Hawaii in coralline formations. A description of early dewatering practices includes a number of case histories; later dewatering practices also are detailed with case histories. There were disasters and some successes. Grouting generally was not successful. Deep wells are technically feasible and generally the economical solution to deep basement construction.

Jan 1, 1986

By Yvone Franco Crosato

The dense population of Hong Kong requires the construction of tall buildings in reclaimed areas or perched on the slopes of the many hills. The large loads to be supported are carried by deep foundations. Many of those are bored piles, to rock, of diameters up to the 3.0 m. of today.

Jan 1, 2000

By Martin J. Kenwright

Within the famous Harrods department store, a new lift shaft has been constructed, servicing a depth of 22m below ground level as well as the existing 6 storeys of the store. The shaft will connect with a new goods tunnel which is to be excavated beneath the shop, as well as new floor space above ground level which has resulted from the infilling of a previously existing lightwell within the store. The construction of the deep shaft while maintaining uninterrupted use of the store by the Client led to a number of innovative solutions being undertaken. Empirical assessments were made of settlements anticipated from the construction process, which took place within a congested environment of existing foundations. Various elements were designed and installed to mitigate the effects of the inevitable ground movement on the surrounding overlying structure, which supported sensitive high quality finishes and mechanical and electrical installations The reinforced concrete lining of the shaft was contained within a cofferdam of minipiles. The minipile placement accuracy (1 in 150) was vital as it could not interfere with the subsequent tunnelling works. As the scheme progressed this became even more critical since the minipiles were needed as support for parts of the permanent works This paper describes:- the high quality placement and control of the minipiled cofferdam, the methods employed in assessing ground movements and the techniques used to mitigate against the effects of these movements.

Jan 1, 2000

By Mike Muchard

Augered cast-in-place piles are one of the most cost effective deep foundation options available to designers but have been largely underutilized due to skepticism associated with quality assurance and hence capacity. When installed correctly, unit friction values can rival any other competing foundation system. To this end, many means have been implemented to increase confidence in the competence of the foundation. One such method is load testing via the Statnamic test method. This paper presents an overview of the Statnamic test method, advantages and disadvantages of its use, and several case studies where Statnamic testing of augered cast-in-place piles confirmed quality construction, brought about design changes, or proof tested problematic installations.

Jan 1, 2000

By SungJe Chi

Intrinsic remediation is the effect of natural attenuation mechanisms - dilution, dispersion, sorption/precipitation and biodegradation - reducing contaminant concentrations in ground water to specified levels at predetermined compliance points in the aquifer. Current monitoring and modeling for post closure was used to assess the current and long-term potential of intrinsic remediation of contaminated seepage originating from a large reactive (sulfidic) tailings impoundment near Questa, New Mexico. It is concluded that the natural attenuation mechanisms of precipitation within the tailings (as a result of buffering) and dilution/dispersion within the aquifer are currently active and likely sufficient to reduce contaminant concentrations to below state standards in the long-term. Other natural attenuation mechanisms such as sorption and biodegradation within the receiving aquife4s) were not assessed here, but are likely further reducing contaminant concentrations. Active interception and recovery of the seepage water is being maintained until monitoring demonstrates that intrinsic remediation has successfully achieved the level of water quality control required.

Jan 1, 2017

By A. Eslami

In recent development of piled raft design, the contribution of both raft and piles to tolerate the loads is taken into account, depending on the stiffness and contributions of involved elements i.e.; piles, raft and surrounding soil. The piles are usually required not to ensure the overall stability of the foundation but to act as settlement reducers. One alternative method of foundation design is therefore to introduce piles purely as a means of improving or enhancing the stiffness of the base soil by structurally disconnecting the piles from the raft. In this paper, two and three dimensional finite element analysis of disconnected pile-raft systems are performed on three case studies including a 12-storey residential building in Iran, a 39-storey twin tower in Indonesia, and the 256m height of Messeturm tower in Frankfurt, Germany. The analysis include different geometrical parameters, e.g., pile spacing and embedment length, arrangement and raft thickness for foundation system to obtain the optimized design functions and to clarify the role of each parameter and method of analysis. The parametric study results and comparison to a few field measurements indicate that by concentrating the piles in the central area of the raft foundation leads to the optimum design with the minimum total length of piles. This achievement can be considered as a criterion for project cost efficiency. On the other hand, disconnected piled-raft systems can significantly reduce the settlements and raft internal bending moments. Finally, the comparison indicates that simple and faster 2D analysis has almost the identical results to 3D analysis which is complicated and time consuming.

Jan 1, 2008

By Robert R. Morrison

Alberta Piling Contractors very rarely are required to perform major marine construction in the prairies, so it became as a big surprise to AGRA Foundations Limited to be invited by Transalta Utilities Corporation to bid on a major marine project for the Sundance Cooling Pond Expansion at Lake Wabamun, Alberta. Even more of a shock, the work had to be undertaken during Alberta's harsh winter conditions with temperatures plunging to -30 C. Not a happy situation for prairie construction workers to be in, working from barges in the middle of a lake in the dead of winter. However, it is well known that prairie boys make the best sailors.

Jan 1, 1997

By Juan J. Campo

The Freeport-McMoRan Main Pass Mine development in the Gulf of Mexico is a complex designed to extract up to 67 million long tons of sulphur over a 40 year period. The initial development includes 15 platforms and 13 bridges located in water depths ranging from 208 to 214 feet, approximately 15 miles east of the Mississippi River Delta. Three additional platforms were designed and installed for the oil and gas development in the complex. Over 110, 000 short tons of steel were required to fabricate the structures. As the sulphur is extracted significant subsidence is predicted over a major portion of complex in the shape of a very large bowl. Vertical elevations are predicted to change as much as 65 feet. Horizontal movements and mudline slope changes cause adjacent platform decks to move as much as 30 feet relative to each other. Differential soil movement is predicted between piling of individual platforms causing the piling to spread, resulting in significant lateral loading on the piling. Relative vertical soil movements are predicted along the lengths of the piles which causes "up drag" or "down drag" forces on individual piles. This paper addresses the design of the piling for the structures in the complex. Design criteria will be discussed explaining how the more traditional offshore environmental and gravity loadings were combined with the unique loading caused by subsidence. Design and analysis procedures will be explained and analysis results presented. These results include the incorporation of 100 ksi steel in thicknesses up to 5 inches in some of the tubular piles. Comparisons will be made between conventional offshore structures and these structures designed to accommodate the subsidence.

Jan 1, 1992

AUSTRALIA CHAPMAN Gary JOHN WAGSTAFF CONTSRUCTIONS PTY. LTD. 1 Ashgrove Crescent 4060 ASHGROVE BRISBANE HILLAR Jaaes Director J.A. HILLAR & ASSOCIATES 99 Woolwich Road WOOLWICH, NSW 2110 WAGSTAFF John Managing Director JOHN WAGSTAFF CONSTRUCTIONS PTY. LTD. 1 Ashgrove Crescent 4060 ASHGROVE, BRISBANE AUSTRIA FUCHSBERGER M. TECHNISCHE UNIVERSITAT INSTITUT FUR BODENMECHANIK Rechbauerstrasse 12 8010 GRAZ

Jan 1, 1994

By Edward J. McNamara

People in the real estate industry are fond of saying that the three most important features of a piece of property are, in order, location, location, and location. This is perhaps the reason that the owners of a well known high-end restaurant chain chose to spend $15 million dollars to renovate 5000 square feet of basement in a 22-story commercial building in the heart of New York City's Time Square. The goal was to create a music club with a stage area and dance floor with a mezzanine level surrounding the dance floor. In order to create the 50' x 40' dance floor and 20' x 40' stage area, 3 concrete columns were removed. New transfer girders were used to transfer the loads of these columns to new steel columns. For the mezzanine, nine columns had to be underpinned. All work continued while the restaurants, shops and offices above carried on business as usual. This paper details some of the means and methods utilized as well as the challenges faced by Underpinning & Foundation Constructors, Inc. in underpinning the columns and installing the new transfer steel.

Jan 1, 2000

By Steven L. Anderson

A cut-off wall has been designed and is currently under construction along the Back Dam of the existing tailings impoundment at Red Dog Mine, Alaska. The cut-off wall, which will be in the order of 5,000 ft long and up to 150 ft deep, when complete, is being excavated using a 40 metric ton Bauer trench cutter head mounted on a Liebherr crawler crane, in combination with a closed loop slurry pumping and de-sanding system. The tailings impoundment is situated in an area of warm permafrost and high potential seismic activity. Design incorporated an assessment of rock jointing to define the final depth of the wall along the alignment requiring the use of plastic concrete backfill to address the concerns associated with potential cracking of the wall due to settlement and during seismic activity. The results of the geotechnical investigation program, particularly with respect to variation in rock hardness along the wall alignment are discussed, as are the design criteria for the plastic concrete backfill, the challenges faced during construction, including scheduling of the work with the on-going dam raise activities of the mine, and the lessons learned with respect to potential productivities and selection of cutter wheels and teeth. Also described are the requirements for and advantages of utilizing a slurry boosting system to meet pumping requirements, re-design of the plastic concrete mix to consider workability and optimization of cutter teeth configurations to reduce wear through highly varied rock hardness.

Jan 1, 2010

By Harry K. Weatherbee

The paper presents a design case study for a four-story correction facility addition in south Boston, Massachusetts, supported on friction piles driven into the Boston Blue Clay. 356 mm (14-in.) square prestressed-precast (PSPC) concrete piles were selected as they were found more effective and economical. A static load test was performed where the pile was brought to "failure". The load test data were evaluated to estimate the Ultimate Pile Capacity as well as the Ultimate Unit Skin Friction (Adhesion) to serve as a design tool for friction pile projects in the south Boston Area.

Jan 1, 2003

By Frank Rausche

Since the early 1980s, when the Road Construction Authority of Victoria authorized the dynamic proof testing of roughly 100 drilled shafts of 1.5 m diameter and typically 60 m length in Melbourne Australia, dynamic load testing has been applied worldwide for quality control of drilled shafts. Today, test capacities of 4000 tons or more are not unusual. On numerous occasions the authors have been involved in similar tests in the United States and test engineers from other countries have reported on experiences in many different countries. Without doubt, generating high test loads is most economically accomplished by dynamic load testing and this method is particularly well suited for testing piles founded in rock because of the rocks low energy dissipation. However, deep foundation professionals have on occasion expressed reservations about subjecting a drilled shaft to impact loadings fearing, for example, a degradation of the shaft ? rock interface properties or potential error sources due to uncertain concrete properties or shaft geometry. This paper will present numerous case studies, demonstrating the performance of rock socketed drilled shafts under dynamic loads. It will discuss the mechanics of the dynamic tests and the method of data interpretation, addressing the concerns stated above and investigating the limitations of the test method. The paper will formulate a set of recommendations for the design and execution of these tests.

Jan 1, 2006

By Peter McDonald

In 1994 the world's largest underwater tunnel was constructed to link Canada and the U.S.A. This new tunnel was large enough to accommodate double-decker railway cars. The construction of an unplanned Retrieval Shaft was required to allow removal and servicing of the Cutterhead of the Tunnel Boring Machine before it passed under the St. Clair River. This paper, which is a revision of that published in Canadian Tunnelling, has been modified here to emphasize construction considerations and describes the evolution of the design and construction of this "Rescue Shaft" under extreme schedule pressure, and changed ground conditions..

Jan 1, 1997

By David Winter

The geotechnical design, construction, and monitoring aspects of a tied back excavation 85 feet deep in Seattle, Washington are presented. The excavation was completed in overconsolidated deposits of sand, silt, and clay. Lateral soil pressures used in shoring wall design were the lowest to date for an excavation of this size in Seattle. Instrumentation data collected from hydraulic load cells and inclinometers were analyzed and are discussed. The data suggest the actual soil pressures felt by the wall were lower than the design values. Recommendations for future study, as well as future design modifications are given.

Jan 1, 1987

By Makoto Kimura

Failure tests on laterally loaded single and pile group are analyzed with a 3-dimensional elasto-plastic finite element program. In the analysis, the mechanical behavior of the ground is supposed to be elasto-perfect plastic with Drucker-Prager's yielding criterion. The nonlinearity of the piles is simulated by assuming a hyperbolic relation between the bending moment and the curvature of the piles. The influence of the axial stress on the cast-in-place concrete piles is also considered in the numerical analysis. It is found that the mechanical behavior of the piles subjected to lateral loading, such as the load-displacement relation up to an ultimately large deformation, and the distribution of bending moment in the pile group can be well simulated.

Jan 1, 1996