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By Ana Pereira, Naomi Norris, Donald Bruggers

The city of Christchurch, New Zealand is predominantly founded on alluvial sediments consisting of interbedded layers of loose to medium dense sand, soft to stiff silt and clay mixtures, and pockets of organics. These soil deposits have high liquefaction potential. Following the 2010/2011 Canterbury Earthquake Sequence several ground improvement trials were undertaken within Christchurch to understand the effectiveness of different types of ground improvement in these silty sand geological conditions. This paper presents a discussion of a stone column ground improvement trial undertaken at a Christchurch site with high fines content soils. Stone columns were installed using two types of installation methods and a range of Area Replacement Ratios (ARR) to assess the effectiveness of these ground improvement methods in high fines content soils as well as the influence on the type of installation method. Pre- and post-column installation CPTs, seismic Dilatometer Tests (sDMTs), cross-hole shear wave velocity tests, and plate load tests have been undertaken to assess the effectiveness of the ground improvement. Results of the testing are presented in this paper. INTRODUCTION This paper presents the results of a stone column ground improvement trial undertaken in Christchurch, New Zealand (Fig.1). In 2010 and 2011, four large earthquakes (greater than magnitude 5.9) and thousands of smaller aftershocks occurred in the greater Christchurch region. These events are referred to as the Canterbury Earthquake Sequence (CES). Liquefaction occurred across large portions of the city during the stronger earthquakes, particularly the February 2011 event. Following the CES a large amount of data was collected across the city including the location and volume of sand boils, and the location and magnitude of ground cracks. Additionally, data from thousands of ground investigations have been uploaded into a public database. As a result, there is clear evidence that silt and silty sands liquefy in addition clean sands. The CES and resulting liquefaction motivated a series of studies and trials from different organisations aiming to better understand the available technologies for liquefaction mitigation. The subject of this paper is a ground improvement trial undertaken by a local contractor specialising in deep foundations and ground improvement. They were interested in understanding the effectiveness of stone column ground improvement in high fines content (silty) soils using two different installation techniques, vibratory and non-vibratory. Different arrays and Area Replacement Ratios (ARRs) were used for each of the two methods of columns installation.

Jan 1, 2019

By Jeff Starchuck, Harald Kullmann

"In 2005, an inspection showed that the Deception Bay Wharf in the Canadian Arctic was at the end of its service life. Although Deception Bay is closed with landfast ice up to 5 ft thick, shipping operations continue year-round, with additional voyages in the summer open-water season to supplement mine supplies. The rehabilitation scheme that allowed minimal interruptions to shipping involved concrete caissons cast on barges and an ingenious placing system.WorleyParsons Westmar of Vancouver, B.C., performed the inspection under contract to the owner, Xstrata Nickel, Montreal, Quebec. The wharf, on the coast of the Nunavik region of Quebec, was originally constructed in 1971 for an asbestos mine, and is now used to support Xstrata’s Raglan nickel mine, importing fuel for p o w e r g e n e r a t i o n a n d general mine supplies, and exporting nickel concentrate to smelters in the south. Emergency repairs were essential to allow operations to continue at the site, while the parties considered permanent rehabilitation options and secured funding. The repairs were done in the openwater seasons, and included reinforcing the failed interlocks above water level with steel patch plates and injection grouting of the cell fill below the port crane in 2005. In 2006, workers installed a circumferential belting system below water level.Westmar held critical planning sessions with the mine operation personnel to find ways to stretch the limits of the mine supplies and nickel storage facilities. In the end, the parties agreed to shut down construction activities four times during the ice-free season to allow access to the dock site.Westmar developed a plan that allowed mine operations to continue during construction, and Xstrata approved the plan and budget in September 2006, for execution in 2007. Rapid construction was essential. To accommodate the short construction season and maintain minimum levels of service for the mine, the work was radically different from conventional Arctic deep-sea port construction. Like the original Deception Bay Wharf, construction practice was to use steel sheet pile circular cells with the consequential heavy support services for the labour force. Construction duration was typically two seasons. The plan for Deception Bay was executable in one season based on a concrete caisson structure. Only a modest amount of schedule float was needed."

Jan 1, 2009

By Dardis J. T. II, P. G. Reinhall

"Impact pile driving of steel piles in marine environments produces extremely high sound levels in the water. It has been shown that current pile driving noise attenuation techniques provide limited noise reduction because significant noise is transmitted through the sediment into the water. To solve this problem, we have developed a double walled pile to decrease the total noise transmitted into the water.The double walled pile consists of two concentric tubes connected by a special driving shoe, allowing for an air gap between the two tubes. The double walled pile is driven into the sediment using traditional equipment by striking the inner tube only. The air gap between the inner and outer tube prevents the radial deformation wave produced by the pile hammer from interacting with the water and the sediment. In one embodiment of the double pile design the inner tube can be removed and repeatedly reused.In this paper we report on the results from a recent full scale field test in Puget Sound, Washington. The use of these double walled piles reduces the peak sound pressure over 20 dB relative to single walled piles. We also show that only a 3 to 6 dB reduction is obtained when a bubble curtain is used on a single walled pile.INTRODUCTIONImpact pile driving of steel piles in marine environments produces extremely high sound levels in the water. It has been shown that current noise attenuation techniques provide limited noise reduction because the noise from pile driving is transmitted through the sediment into the water. In [1,2] we showed, using modeling and field data, that the primary source of underwater sound from an impact driven pile originates from radial expansion of the pile as the compression wave propagates down the pile after each strike. The radial expansion is coupled to the compression wave through the Poisson’s ratio of steel. As discussed in [1], the supersonic radial expansion wave (with respect to the water) produces an acoustic field in the shape of an axisymmetric cone, or Mach cone. We showed in [3] that the ability of any sound shield that surrounds the pile in the water only (such as a bubble curtain or a surrounding double wall engagement) to attenuate the sound in the water is limited by the fact that an upward moving sound Mach wave is produced in the sediment and is transmitted into the water. To improve the performance of bubble curtains and other noise shields in the water, it is necessary to attenuate the noise emanating from the sediment into the water. Figure 1 illustrates how sound from the seabed leaks out from the sediment, limiting the effect of the surrounding bubble curtain."

Jan 1, 2017

By Charles M. Wilk

"Mass stabilization (MS) is a ground improvement technique that can prepare areas of low bearing strength soil for subsequent infrastructure development. The technique involves mixing binding agents such as portland cement, fly ash, slag, or lime into the subject soil while the soil remains in-place (insitu). The binders “cement” the soil grains together to form a cement modified soil or a soil cement. The MS-treated area now has improved bearing capacity to support infrastructure or to prevent movement of the material such as landslides.The same insitu soil mixing technique can be used to address contaminated areas. Binders or reagents are mixed into soil. The treatment protects human health and the environment by immobilizing hazardous constituents within the treated material. When used for the purpose of environmental remediation the technology is called Insitu Solidification/Stabilization (ISS).Both Mass Stabilization and ISS treatments require laboratory studies to develop a mix design of soil and binder(s) that produce the desired physical and/or chemical properties. The mix design is then transferred into the field. Successful MS and ISS treatments rely on reproduction at full-scale of the mix design and the thorough mixing attained at laboratory scale. Fifty to 70% of the cost of a MS or ISS project is in the cost of the binding agent that is to be mixed into the subject soil. Under-dosing, overdosing, non-thorough mixing, and mixing in the wrong areas all create cost over-runs.This paper will discuss recent innovations in mass stabilization systems that improve the cost effectiveness of the treatment technology. Specialized equipment can impart greater mixing shear thus improving the thoroughness of mixing. Dry powder pressure feeders can conserve the “drying capacity” of binder resulting in higher strengths at lower binder dosages. Global Positioning System (GPS)-based systems can guide the mixing operator for complete mixing coverage. An integrated tracking and feeding system can record that proper dosing and mixing was accomplished and generate construction QA/QC reports for the client.INTRODUCTIONNew or expanding infrastructure projects may encounter areas of low bearing capacity soil or areas where marginal materials such as waste, dredged material, or sediment have been placed. Mass stabilization is a geotechnical method that can be used to improve the bearing capacity or stiffness of soil. Mass stabilization involves mixing binding agents into soil subject to treatment while the soil remains in-place or insitu.Mass stabilization technique can also address contaminated soil therefore, the same technique can be used to attain both civil and environmental engineering goals. In this environmental application the technology is known as insitu solidification/stabilization (ISS). ISS protects human health and the environment by immobilizing hazardous constituents within the treated material."

Jan 1, 2015

By Kamil Nuzha, Jianchao Li, Bashar S. Qubain

"The Philadelphia Water Department is rehabilitating Belmont Raw Water Basin. As part of this work, a 500-ft long, temporary cofferdam was designed to retain 35 ft of combined water and soil at the western half during the reconstruction of the eastern half. A cofferdam that comprises two integral rows of sheet piles was selected to take advantage of the soil’s weight between the sheet piles for increased stability. To fine tune the design, a geotechnical investigation was carried out to verify the subsurface conditions and, in particular, the top of rock variations along the centerline of the cofferdam. A detailed finite element analysis was performed based on the subsurface findings and incorporating the construction sequence to evaluate the behavior of the cofferdam at the following stages: installation of tie rods to connect to the two rows of sheet piles; partial excavation and installation of tiebacks; complete excavation of the east basin, and demolition of the cofferdam. Inclinometers and survey markers were installed every 100 ft along the cofferdam and were monitored throughout construction. The deformation measurements were in good agreement with the finite element results.INTRODUCTIONThe Philadelphia Water Department (PWD) Belmont Raw Water Basin is located at the intersection of City Line and Belmont Avenues in Philadelphia, PA. The facility actually contains two raw water basins, east and west, separated by an earthen dividing dike. Water leakage at the bottom of the basins and through the dividing dike together with increasing demand for a larger storage capacity dictated the replacement of the wide earthen dike with new narrower concrete structure. The temporary cofferdam was designed for a two-year period to facilitate excavation support, water cutoff, removal of the existing earthen dike and replacing it with a new concrete dike. During this construction sequence, the water level in the west basin had to be maintained at or near its full capacity.Various excavation support systems were considered for this project prior to the selection of a double wall sheet pile cofferdam. Fig. 1 shows a plan view of the cofferdam and the new dividing dike. A typical cross section of the two structures is shown in Fig. 2. Double row sheet pile walls are commonly used as both temporary and permanent retaining systems in open water applications such as construction works, quaywalls, breakwaters and revetments for storing industrial waste as indicated by Ohori, et al. (1984), Ohori et al. (1988), and Khan, et al. (2001). There are many advantages to double row sheet pile systems as recognized by Ohori, et al. (1984; 1988): (1) It can be installed and removed in the presence of water easily and quickly; (2) it provides stability with small width to height ratio, utilizing the existing soils between the installed sheet pile rows; and (3) it serves well as a means for water cutoff. These advantages meet the specific project requirements."

Jan 1, 2016

By K. Ronald Chapman, Claus Ludwig, Doug Jenevein

"In the spring of 2005 Schnabel Foundation Company completed a $15.2 million Design/Build subcontract to underpin 11 structures, and provide 202,800 square feet of earth retention for the Reno Transportation Rail Access Corridor (ReTRAC) project in Reno, Nevada. Schnabel’s work was part of a Design/Build contract to depress a railroad alignment through downtown Reno. The depressed section was 2.2 miles long, 54 ft wide, and up to 35 ft deep (3.5 km long, 16.5m wide and up to 10.7m deep). The trench structure was required to be watertight. SUBCONTRACT WORK OVERVIEWEleven buildings along the track alignment required underpinning. Three types of underpinning were used, designated Type 1, Type 2 and Type 3.At four buildings the trench retaining walls were to be located directly under the exterior footings. This alignment eliminated traditional underpinning and cut-off wall techniques that could normally be used to support structures. Type 1 underpinning was used at these buildings. This underpinning system consisted of a combination of permeation grouting, hand-dug piers, and permanent tiebacks. This underpinning system became the new watertight trench walls.Five buildings were located a few feet behind the trench walls, and their exterior walls were supported by continuous footings. Type 2 micropile/pile cap underpinning (patent pending) was used to support these buildings.The remaining two buildings were also located a few feet behind the trench walls, but they had column footings along the exterior walls. At these structures traditional micropile underpinning was provided through the existing footings. This is described as Type 3 underpinning.Temporary earth retention was required on both sides of the trench along most of the alignment. This shoring supported frontage roads, private property and surcharge from the temporary railroad shoofly running parallel to one side of the trench.SUBSURFACE CONDITIONSThe soil along the trench alignment consisted of river outwash deposits. The top 2 to 18 feet (0.6m to 5.5m) generally consisted of flood plain silt and sand deposits, or fine-grained fills. These fine-grained soils are underlain by the Tahoe Outwash Formation which consists of interbedded layers of sand; sand and gravel; and sand, gravel, cobbles and boulders. Some of these layers encountered during construction consisted of 30 to 50 percent cobbles and boulders, with some boulders up to eight feet in diameter.A major challenge to the design and construction of the trench structures and the underpinning was the ground water table which was 10 feet (3m) above subgrade in the deepest portions of the trench. Based on specification restrictions, temporary and permanent dewatering was not feasible. As a result, the selected design and construction methods had to consider three water conditions: the anticipated groundwater level during construction (CGW), the groundwater level for permanent design (DGW), and an additional special design condition with water at street grade."

Jan 1, 2006

By Kaushik Mukherjee

"Malaysian offshore and surrounding region are favorable to the installation of driven piles. During the design phase, pile driveability analysis plays a major role in pile make-up design to suit and selection of the feasible hammer, besides defining acceptance criteria to ensure a certain level of confidence of its fitness for purpose. The accuracy level of driveability analyses depends substantially on the selection of its parameters that best represent the in-situ scenario. The most uncertain of the parameters are those related to the soil model. It is noted in various projects in the region, that the consideration of suitable soil resistance to driving, coupled with soil dynamic parameters, significantly affects driving sequence planning, design, material, hammer selection and most importantly pile acceptance criteria. This is particularly relevant for a region that contains predominantly clayey subsoil resulting in large diameter, long friction piles susceptible to driving disturbances and slow strength recovery. Various researchers suggested suitable dynamic parameters and soil resistance during driving calibrated to specific regions. Regional experience suggests a set of soil degradation and parameters to suit the different stages of driving which is corroborated by pile monitoring records during continuous and delayed driving scenarios. The most sensitive amongst all dynamic soil parameters is the skin damping in clay. Smith’s wave theory approach considers a conservative assumption in selecting the parameters in absence of site-specific data, while a different approach may be adopted based on consistency of the clay for a site where the geotechnical parameters are well defined. This paper summarizes some independent studies on the effects of variations in dynamic parameters and resistance at different stages of driving and suitability of choices of different pile make-up and hammers for an optimum design. Similar experiences, coupled with simulation studies and back-analyses of available driving records suggest a reasonable judgment for the region.INTRODUCTIONFixed structures are generally supported in the in-place condition on a pile foundation those may either be driven or drilled & grouted piles depending on the subsoil. The piles may be driven inside the jacket legs or drilled through individual skirts normally grouped in clusters at the base of each leg. The types of subsoil dealt with in the Peninsular Malaysia and Gulf of Thailand surrounding region are conducive to the installation of driven piles only. The design of an offshore pile is fundamentally the optimization of pile length, size and make-up those are suitable to the requirement and supply. An interactive effort combining aspects related to geotechnical, structural and constructability are required to converge into a feasible, safe and economic solution. Other than the checking of the installation feasibility using a set of hammers in a given environment, driveability analysis is also used to define acceptance criteria for a majority of the offshore piles. Unlike short and end bearing piles in sand/soft rock, the piles in clayey subsoil regime often could not be rested on a dense strata where it could be met by a definite set criteria. Usually a measurement of blow counts determined and defined by driveability analyses forms the acceptance criteria to ensure a certain level of confidence of its fitness for the purpose coupled with an optimum penetration. While softness and uncertainty of the soil strata at target penetration may be resulted in possible overdrive, an unusual delay or the presence of an unidentified cemented layer or a boulder may cause early refusal or underdrive scenario. Hence, accuracy of the investigation, driveabilty study as well as the precautionary measures to avoid delays during driving are of equal importance."

Jan 1, 2015

By Sebastian Lobo-Guerrero

Welcome to DFI45! our first on-line annual meeting. We cannot deny the severe impacts that the COVID19 pandemic is having in our industry and our lives. We extend our support to all of our members that have been impacted in many different ways. But through the middle of this difficult and challenging times, our beloved annual conference emerges, trying to re-unite our industry and remind us why we love what we do so much. DFI45 was not originally planned to be delivered virtually, but as our world changed, we adapted. Adversity became an opportunity to re-invent our annual conference. Thanks to the vision of our Organizing Committee, we saw the amazing new possibilities and DFI45 is today a reality. Our theme for this year is People + Purpose + Passion. This theme was decided before the COVID 19 pandemic started, but today it is more relevant than ever before. We are a group of very diverse people at DFI. Our organization includes Contractors, Consultants, Suppliers, and Academics just to name a few sub-groups. But we all have a common purpose and try to find common ground. We are all extremely passionate about what we do, and this excitement is really what makes this organization what it is today. This conference celebrates this passion as you can see in our three main Keynote Sessions. On a local scale, we want to go back and remember the contribution of our industry to our beloved National Monuments in Washington D.C. On a national scale, we want to explore and recap the development of Government Guidelines and Specifications that became the world standards. And finally, we want to close the conference with a session celebrating the family legacy and share amazing stories of families with multiple generations working in our industry. Besides our Keynote Lectures, the conference is full of exciting content such as several case histories, experimental research in deep foundations, applications of new technologies, business aspects and risk management considerations for deep foundations, just to list a few. We also have our now traditional events such as the Hal Hunt Lecture, Awards Reception, DFI Educational Trust 5K Fundraiser, etc. For the first time, all this content will be delivered using different virtual formats, including on-demand presentations, plenary sessions, interactive chat rooms, etc. We are excited about these possibilities. To conclude, we need to recognize the people that against all odds made this conference a reality. First our sponsors, they adapted to the most abrupt change never thought before, and they always stayed there with us, providing unconditional support. Without them no conference is possible. Next, our Organizing Committee that re-invented the concept of an annual conference and found new and exciting ways to make this happen! Our Technical Program Committee led by our Technical Program Chairs, Jennifer Nicks and Gregg Piazza, showed us that nothing is impossible. And last, but not least, the amazing DFI staff that make dreams reality. It has been an honor to serve as the Conference Chair for DFI45. It is an experience that will stay with me for the rest of my career. Conference Chair: Sebastian Lobo Guerrero, Ph.D., P.E. American Geotechnical and Environmental Services (A.G.E.S.)

Oct 27, 2020

By Alice Y. Tseng, Dan MacLean

"Corrosion protection of all deep foundation systems made of steel is THE issue when considering durability of the element in the long term. Protecting steel from corrosion and maintaining the steel tendon cross sectional area ensures a competent and durable system. The foundation of a building is usually difficult to repair and therefore high risk is taken when unknowingly choosing a non-adequate solution.Requirements according to EN 1990 (Eurocode 0 or EC 0) on construction durability requires a service life over 100 years. How can a service life over 100 years be achieved? How shall bare steel be protected in soil, which sometimes could be an aggressive environment to the steel? Which corrosion protection methods are commonly used in Europe and in North America?This paper will focus on hollow bars used as Micropiles, Anchor piles and Soil Nails. It gives an overview about the state of the practice in regards to corrosion protection (including head construction) and evaluates different options following the European Standards focusing on type of material and method of installation. Further the different corrosion protective methods such as thickness of grout body, coating types and sacrificial loss are listed with the pros and cons evaluated.Based not only on North American standards like FHWA “Micropile Design and Construction Guidelines”, FHWA Geotechnical Engineering Circular No. 7 for “Soil Nail Walls“ and Post-Tensioning Institute “Recommendations for Prestressed Rock and Soil Anchors”, but also European standards like EN 14199 “Execution of special geotechnical works – Micropiles”, EN 14490 “Execution of special geotechnical works - Soil nailing”, EN 1537 “Execution of special geotechnical work – Ground anchors“, and other relevant standards, all possibilities of protecting the hollow bars and the steel quality will be introduced, discussed and compared ."

Jan 1, 2017

By Abolfazl Eslami, Sara Heidarie Golafzani

CPT-based methods considered as complementary tools for static analyses outperform other axial pile bearing capacity predictive methods. Considering soil spatial variability and minor errors associated with procedure and operator, CPT-base methods mitigate the effect of latent uncertainties in pile design. These methods were developed based on different databases and purposes. Hence, several statistical and probabilistic attributes were defined and implemented to assess the predictive CPT-based methods’ performance via CPT and pile databases in terms of the model parameter. These features make a comparison among methods in terms of precision, accuracy, and efficiency. Furthermore, CPT-based methods can be subjected to scrutiny over their backgrounds and how they were developed via reliability analysis. In this regard, a database of sixty-two driven piles and their adjacent CPT soundings were gathered, and six commonly applied CPT-based methods were examined according to criteria other than prevailing statistical and probabilistic ones, including; (a) input variables, (b) soil behavior classification (SBC) (c) model assumption (d) Influence zone, and (e) axial loading direction. According to these introduced criteria, CPTbased methods were classified and appraised via efficiency ratio. Eventually, these reliability-based, statistical, and probabilistic criteria evaluate the understudied methods performance for the investigated compiled database and help designers select consciously appropriate predictive methods according to the site conditions.

Sep 8, 2021

By Todd Nottingham

Channel deepening of major ports is challenging designers to explore innovative solutions to ensure stability of bulkheads, such as for the Oakland Inner Harbor. This particular challenge was met with the use of the SPIN FIN® Tension Pile for restraint of an HZ combination wall along the Oakland Inner Harbor Shoreline in Oakland, California. A SPIN FIN pile is a pipe pile with welded plates at the pile tip that increase pile capacity. A brief history of the project will be provided as well as results of pile load tension tests, pile strain gauge, and wall deflection under construction loads. Tension pile load deflection results will be discussed with recommendations toward establishing deflection-based ultimate load criteria. A discussion of predicted wall loads and field observed wall loads will be provided.

Jan 1, 2008

By Alberto Carmona Rosell, Sri Ram Ramankutty

"The installation of Bored Piles and Diaphragm Wall under slurry using tremie raises quality concerns on the integrity of concrete. It is vital to understand the effects on concrete integrity during concrete pouring process. This paper intends to unveil to what extent the compressive strength of the concrete pour is affected in contact with drilling fluid still. Another important angle of analysis proves whether the inclusion of solids particles of un-hydrated fluid could have impact on the concrete compressive strength. The testing comparing the response of concrete compressive strength when drilling fluid is included into the concrete mix altering the water/cement ratio by 5%, 20% and 30%. Comparative results are analysed between two different hydrated slurries namely sodium activated Bentonite and 3rd generation synthetic polymer.1. INTRODUCTIONSoil stabilization is the base for a successful deep foundation execution. The G3 System Slurry developed by Ground Engineering Operations (GEO), with its third generation polymer, namely PolyMud®, is an innovative and unique alternative to the mineral based slurries for soil stabilization, enhancing the quality and integrity of the underground foundation structures. It optimises the production rate of work progress and cost as well. At the same time, PolyMud® slurry is proven to be environmentally friendly.Guaranteeing the maximum quality of the foundation elements according to the initial design is one of the most important objectives and a concern for the foundations contractors. In order to fulfil the project expectations in this aspect, any incident that could compromise the designed concrete integrity and capacity must be avoided.GEO, has carry out its own research regarding effects on the concrete compression results if drilling fluid intermixes with fresh concrete while pouring. To shed light in this regard, GEO, in collaboration with CML (Concrete Materials Laboratory) Sdn. Bhd., carried out empiric tests that analyse this particular event from different perspectives, bringing up the corresponding results that will be studied and commented in this article."

Jan 1, 2015

By Hiren J. Shah

Across much of New York City, the geology of glacially deposited soils follows a common sequence. Outwash sands generally overlie varved silts and clays, which lie above a basal till deposit underlain by the bedrock. Pile foundations at projects with such typical stratigraphy generally develop their axial capacities by extending below the fine-grained deposits into the till or the bedrock. Contrastingly, at a project site on the Brooklyn waterfront, high capacity piles were efficiently and economically installed by driving them into the relatively shallow glacial drift and till deposits which lay above thick fine-grained compressible glacial lake deposits. An unusual aspect about the foundation design at the Brooklyn project site is that, relatively short and high capacity piles were driven into the shallow glacial drift and till deposits, overlying the thick fine-grained glacial lake deposits. In order for this unusual foundation scheme to be feasible and economical, the piles needed to achieve their driving criteria in the upper strata. Consolidation settlements in the lower stiff and over-consolidated glacial lake deposits below the pile tips had to be relatively small. The paper discusses the unusual stratigraphy in this area of Brooklyn in greater detail with geologic profiles and engineering characteristics of the glacial strata. It also discusses the design aspects of the pile foundations, settlement estimates, a pile drive test program during design, results of the static load test program during construction, and production pile installation results.

Jan 1, 2008

By Yahia M. Al-Smadi

Effect of lateral loading against existing sheet pile wall and distribution of gravity loading due to various number of construction loading scenarios were studied. The objective of this effort was to determine the loading case that permits the contractor to utilize a 400 ton crane at the specified location with the existing limitation imposed on site. Staged analysis was determined as the methodology that will more accurately predict the exiting and additional stress due to the impose crane loading. A reliable and robust analysis (ANSYS) software was used to complete both 2D and 3D finite element model and analysis. Analysis model parameters such as material properties, non-linear behavior of the soil, and meshing are presented and discussed. At the conclusion specific range of crane operation and pick weights operating on existing concrete mat supported on top of an existing tunnel was reviewed and deemed acceptable.

Jan 1, 2010

By William B. Conway

This paper will describe the large caisson pier foundations for four of the bridges crossing the Mississippi River in the New Orleans area; and will discuss some of the unusual problems encountered during their sinking. Certain settlement phenomena experienced during their service life will also be related: The four bridges in order of their construction: The Huey P. Long Bridge, River Mile 106.1, completed in 1935 The Greater New Orleans Bridge No. 1, River Mile 96.0, completed in 1958 The Hale Boggs Bridge, River Mile 121.6, completed in 1983 The Greater New Orleans Bridge No. 2, River Mile 96.1, completed in 1988 Each of these bridges employed large open-dredged concrete caissons as foundations for one or more of the river piers, with the smallest being the 65ft by 102ft caissons for Piers I and II of the Huey P. Long Bridge and the largest being the 99ft by 214ft caisson for Pier II of the Greater New Orleans Bridge No. 2. The Huey P. Long caissons are founded in a dense fine sand at -170 while all of the other bridge caissons are founded in hard preconsolidated clay at elevations varying from -150 to -185. The Huey P. Long Bridge is currently being widened without increasing the caisson foundations under any of the river piers; and the design reasoning that led to this decision is presented.

Jan 1, 2013

By Jon E. Bischoff

Construction of a secondary clarifier on the banks of Rainy River, Northern Minnesota, required the driving of H-piles 14HP102 to a sloping, very strong bedrock through thick deposits of soft and medium stiff soils. Pile toe protection, APF Hardbite HP 77750, was specified to prevent damage to the pile toe and to enable the pile toe to bite into the bedrock surface. The toe protection worked well for bedrock sloping less than 2H:1V. However, where the bedrock was steeper, the piles experienced damage and failed to reach bearing. In most cases, the also the replacement pile failed. Pile Driving Analyzer measurements showed that on encountering the bedrock, the pile toe reflection, which at first was sound, deteriorated indicating pile toe damage. Extraction for visual inspection showed that the failed piles were bent and had deformed pile shoes. In areas of steeply sloping bedrock and for replacement piles, an alternative shoe, the Scanpile Herkules rock shoe, was employed. This pile shoe proved to be able to secure the pile toe into the rock and to eliminate the problem. The costs of the Herkules rock shoe considering price, shipping, and attaching, were about equal with the Hardbite shoe.

Jan 1, 1993

By Hyunsuk Yoon, Kiho Lee, Juhyng Lee, Younghoon Jung, Junboum Park

"The environmental double pile method is presented as a device to improve the engineering properties and to clean up contamination of low-permeability soil. This method is one of the novel technologies based on the concept of one step process. It can be applied to low permeable contaminated ground for site reuse. It uses piles to improve drainage, contaminant remediation, and bearing capacity of the ground. To evaluate the on-site applicability of this technology, drainage and strength properties of the environmental double pile were assessed by a series of experiments and numerical analysis. Environmental double pile was found to be a feasible alternative method to improve contaminated soft ground.Korea is a peninsula with many coastal industrial zones. These zones are located in regions mostly underlain by soft ground with low permeability and adjacent to industrial areas that can be contaminated. Therefore, a new region-specific remediation method is required to achieve environmentally sustainable development. This research introduces the Environmental Double Pile (hereinafter, refer to as EDP) for the lowpermeability contaminated ground and focused on both contaminant remediation and soft ground improvement. Basically, the EDP is quite similar to sand compaction pile (SCP). The SCP has been studied extensively to improve soft ground (Braja 1999; Hansbo 1994; Madhav and others 1978; Taylor 1948). But unlike SCP, EDP is filled with oyster shells instead of sand and an inner pile is inserted in the center of this oyster shell filled-zone. Therefore, it is a double pile consisting of the oyster shell pile and the inner pile, as depicted in Fig. 1."

Jan 1, 2005

By J. H. Qian

China is one of the countries with comparatively wide distribution of soft soil. In the wake of the rapid developement in the national economy and construction, the improvement technique of soft soil foundation has been perfected gradually. At the present, an integrated system of soft soil improvement has formed, features of such a system are shown by the variety of improvement methods, the complement of theoretical study to project practice. This paper summarizes mainly the following methods: lime column, vertical drain, vibroflotation and dynamic consolidation.

Jan 1, 2010

By John G. DiGenova

The Allwell Center Ice Arena at Plymouth State University, Plymouth, New Hampshire is located in the flood plain of the Pemigewasset River. To maintain the arena near the level of the surrounding area, foundation design required use of uplift elements to resist hydrostatic loads caused by frequent flood conditions. Soils beneath the arena consisted of very loose to medium dense alluvial deposits overlying thick glaciolacustrine deposits. Bedrock was encountered at depths of 115 feet (35 m) or more. A mat foundation with a sealed building system was developed for the arena to guard against flood events. Several alternatives were investigated to provide uplift capacity for the mat foundation, including the Rammed Aggregate Pier® (RAP) system, driven precast-prestressed concrete piles, driven H-piles, and deep drilled soil/rock anchors. Evaluations indicated that the most cost effective uplift solution was a tension RAP system that developed uplift resistance in the shallow alluvial deposits. A total of 344 55-kip (245-kN) capacity RAP elements were required for the project. The RAPs were designed to resist tensile loads using threaded steel bars. Dual corrosion resistance was provided to the uplift elements by including sacrificial steel and galvanizing the oversized bars and connection plates. A pre-construction test program was conducted on RAP elements drilled to a depth of approximately 25 feet (7.6 m) and installed using various shaft construction procedures and materials. Ten test piers were constructed and six were tested to verify that the piers could resist 200 percent of the design load with measured deflections of less than 1 inch (25 mm). The RAP system also provided improved bearing conditions for the perimeter wall and mat foundations by densifying and stiffening the upper alluvial soils.

Jan 1, 2011

By Jim Cook

Arsenal Football Club required the development of a new home stadium in north London, subsequently named the Emirates Stadium. The proposed development comprised a 60,000 seat stadium, with associated facilities and a sports training centre. Described are the foundation solutions and piling construction techniques used, which take into consideration the potential impacts on existing above and below ground railway infrastructure and underground water structures. Methods used by the piling contractor to improve aspects associated with health, safety and quality are also described.

Jan 1, 2008