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By Adnan A. Malik, Tadashi Maejima, Jiro Kuwano

"The use of steel screw piles has greatly increased in recent years because of the advancement in the installation mechanism and its performance under compressive, uplift and lateral loads. In a steel pile system, the strength of pile material limits the end bearing resistance of the pile due to strong subsurface conditions. The installation mechanism of screw pile can reduce the end bearing resistance due to the torque and axial force. However, if the installation mechanism does not reduce the bearing resistance of the pile, another important factor that can reduce its performance is the strength of the helix/wing plate. In this study, the effect of wing plate deformation on the performance of single helix/wing plate pile bearing resistance investigated. A model ground was used to investigate the effect of wing plate deformation. Dry Toyoura sand was used as a ground material and was compacted to denser states of 80% and 92%. The shaft and wing plate material of the pile was the same to actual piles that are used nowadays in Japan. A series of load tests were performed with different wing plate diameters and thicknesses. It was observed that deflection in the wing plate reduces the bearing resistance of the pile. The increase in the thickness of the wing plate was seen to restore the reduced pile resistance due to deflection. It was also observed from the experimental results that the ratio of wing plate diameter to shaft diameter (Dw/Ds) greatly affects the deformation of wing plates, which ultimately affects the end bearing resistance of the pile. The results obtained in this research suggest that the outstand length (Lw) of wing plate should be less than 5.6 times the thickness of wing plate for piles having a large Dw/Ds ratio under strong ground conditions.INTRODUCTIONThe first use of screw pile was almost 180 years ago by Alexander Mitchell. He patented his invention in 1833 with the name “Screw Pile”, and used it for ship moorings. The use of screw piles has since been adopted in various areas such as lighthouses, fencing for agriculture and marine structures. The use of screw piles in civil works started in 1985, after the invention of the hydraulic torque motor, as it eases the installation process. Nowadays, screw piles are used in the foundation of transmission towers, elevators, buildings and many other civil structures.Screw pile has an edge over other steel pile systems due to its high bearing, uplift and lateral resistance. The end bearing resistance of screw pile depends on installation, strength of subsurface material and the pile material. The screw pile is installed by applying torque and axial force. The pile torsional strength should be more than the applied torque and axial force to avoid deformation before reaching the final depth."

Jan 1, 2015

By Rajarshi Pramanik, Nirjhar Dhang, Dilip K. Baidya

"This paper performs the reliability evaluation of pile foundation under vertical loading condition using the concept of fuzzy set theory. The uncertain parameters are expressed as fuzzy numbers. Monte Carlo simulation technique in conjunction with fuzzy set theory and fuzzy reliability index approach are implemented in evaluation of the probability of failure of pile foundations. The results are validated through some well established methods such as, First Order Reliability Method (FORM), Second Order Reliability Method (SORM), and direct Monte Carlo Simulation (MCS). Response surface method (RSM) is used to approximate the original limit state equation through second order polynomial. The effect of the position of the water table is also highlighted. Finally, the effect of the variation of applied load is examined and it is observed that the fuzzy reliability analysis gives more conservative estimate of failure probability than the other methods.INTRODUCTIONCivil engineering structures, such as high rise buildings, bridges, offshore platforms etc. are always subjected to vertical as well as horizontal loads. To support these structures, pile foundations are generally the solution in most of the situation. It transmits load from the superstructure to soil at a reasonably great depth. This transfer may be by vertical distribution of the load along the pile shaft or a direct application of load to a lower stratum through the pile tip. Different methods are available to estimate the capacity of piles embedded in different types of soil and under the application of vertical and horizontal loading. To consider the variability in soil and other unforeseen able situation, generally a reasonable value of factor of safety is used to estimate the designed capacity of the pile. Recent developments have shown a trend to place the treatment of uncertainty on a more formal basis, in particular by applying the results of reliability theory to geotechnical engineering. Keeping in mind the importance of pile foundation in the engineering structures it is essential to maintain a high structural safety which result in increase in reliability. The probability theory has been proved to be a powerful tool for representing variability in mathematical models. The variability associated with soil parameters and the modeling uncertainties are needed to be considered for the reliability assessment purpose.Recent development (Zhang et al. 2005; Misra and Roberts 2006; Haldar and Babu 2008; Basu and Salgado 2012; Teixeira et al. 2012; Pula and Rozanski 2012; and Chan and Low 2012) showed that the reliability analysis of pile foundations subjected to axial as well as lateral load has been one of the important current research topic in geotechnical field. Probabilistic based performance criteria were quantified for a single pile and pile groups in cohesionless soil by Eloseily et al. (2002). A p-multiplier approach was incorporated into the analysis to modify the p-y curve for a single pile to obtain the p-y curve for individual piles in a pile group. A statistical analysis of set up capacity of pile was carried out from the database of a large number of pile testing data in clay by Yang and Liang (2006). Load and resistance factor design (LRFD) using FORM was used for examining the different load and resistance factor for different target reliability index. Limit state analysis of drilled shaft was performed by Misra and Roberts (2006) in probabilistic framework. The fuzzy based reliability analysis (Dodagoudar and Venkatachalam 2000; and Park et al. 2012) of the earth slope was reported in the literature. Dodagoudar and Venkatachalam (2000) presented a new approach, called fuzzy point estimate method (FPEM) for reliability evaluation of earth slope. Park et al. (2012) reported a hybrid approach, fuzzy set theory in conjunction with Monte Carlo simulation technique, to determine the failure probability of earth slope. Second Order Reliability Method"

Jan 1, 2015

By Danny Déry-Chamberland, Peter Bowman, Michael Byle

"The Barrage des Quinze dam is a concrete sluice dam consisting of 19 spillway sections, each of which is approximately 7.6 metres wide and 14.5 metres deep. Rehabilitation efforts being performed on the dam including demolition and improvement of the roadway and spillway sections and grouting to mitigate underseepage. Initially, conventional cement grouting was attempted and was successful in 14 of the spillway sections, but unsuccessful in 5 of the sections due to the high water flows which washed the grout away. The removal of the roadway and portions of the piers during construction temporarily reduced the stability of the structure limiting grouting pressures that could be applied. This and the substantial high water flows (leakage) beneath the dam between the concrete/rock contact and within fractures in the upper rock formation created a challenging situation to create a cutoff.A grouting solution was developed that involved implementing several different grouting methods and materials including balanced high mobility grouts (HMG); low mobility grouts (LMG); polyurethane grouts; and sodium silicates. Because of the critical scheduling for the work, multiple approaches were planned and made available on site so that the work could proceed with the best technology with little, if any, time loss. The end goal of the grouting program was to create a seepage cutoff beneath the 5 sections of the dam in a stepwise process. The initial step was to fill the large openings and create a grout barrier to reduce the high water flow. The second step was to seal the contact between the base of the dam and the bedrock; and the third step was to complete closure by grouting a deep grout curtain into the underlying rock. Other features of the work included an extensive grout mix testing program, water pressure testing, borehole camera survey, and monitoring of the grout injections."

Jan 1, 2016

By Silvana B. Foá

Results from full-scale loading tests showed the use of the dynamic increasing energy test (DIET) to verify the capacity of deep foundations. This method allows the measurement of dynamic resistance - displacement curve and the prediction of the static resistance -displacement curve of the pile-soil system. The comparison between the use of DIET versus the static load test is also considered herein. This work was divided in two different phases, the first accomplished in Salvador (Bahia) and the second in Brasilia (Federal District), both in Brazil. The first phase consisted of field loading tests carried out on piles comprised by an approximate 10 to 12 meters thick deposit of fine saturated sand, overlying a stiff clay layer, which is found in certain areas of the Brazilian Northeast. Two metallic (rail track) piles were field loaded in this site. One of them was dynamically tested and the other was statically tested. The second site belongs to the Post Graduate Program of the University of Brasilia. It is comprised by an approximate 8 to 14 meter think deposit of porous clay, overlying a hard strata of saprolitic state. In this site a unique precast driven centrifuged pile was tested. The DIET procedure has demonstrated to be a tool of fast execution and low cost (if compared to static load test). It is a promising procedure to evaluate the behavior of pile-soil system.

Jan 1, 2002

By Jim Bruce

No answer required. From the drilling equipment suppliers, but the specifications must be tailored to be project-specific. Yes, the sonic technique is very interesting as we said, and it is not so much as an issue of the magnitude of power, it's about the efficient use of the power. The efficiency of the machine is not necessarily related to size so it is best to talk to the two contractors that supply the service about that. I think it can be scaled down but it is quite a big head, so therefore there are practical limitations on the size of the door it can walk through and also the size of the casings and rods that it can use. You might defeat the economic advantages if you were to use too short casing lengths. Boart Longyear have a low head room machine that can work within an 8 foot verical clearance.

Feb 10, 2003

By Peter A. Thompson, Richard E. Prust

"The Bangkok Mass Rapid Transit (MRT} Chaleom Ratchamongkhon Line project is the first underground subway to be completed in Thailand. It consists of 22 km (14 miles) of twin-bored tunnels and 18 cut and cover stations constructed within the deltaic deposits that underlie the city. This paper describes the ground conditions, site investigation, including the use of the self-boring pressuremeter and the associated design issues for the construction of deep foundations. The paper also describes a selection of the various deep foundation solutions that were adopted to address particular constraints of the project and the ground conditions, including slurry walls for the cut and cover stations and foundations used for the underpinning of existing structures.INTRODUCTIONThe MRT Chaloem Ratchamongkhon Line Mass Transit Underground Railway comprises approximately 22 km (14 miles) of tunnels and 18 stations. The route is shown in Figure 1.The project was divided into two design and build contracts. The northern section was awarded to the ION joint venture, composed of Italian-Thai Development PLC, Obayashi Corporation and Nishimatsu Construction Co Ltd. Arup were contracted by ION for the design of the northern section. The section comprises 11 km (7 miles) of twin-bored tunnels, nine cut and cover station tunnels constructed within perimeter slurry walls using top down construction methods, and two cut and cover tunnel structures.The majority of the route of the northern contract follows existing highway Rights of Way. This results in the tunnel alignment passing through the foundations of existing highway bridge structures for which a variety of deep foundation solutions were adopted to underpin these structures.An 8-story park and ride building in the Lat Phrao area was also constructed using deep foundations."

Jan 1, 2005

By Adrian Mercer, Ashkan Ameri

Due to general degradation, increased traffic levels, and historical ground movement, this road and rail bridge which provides an essential link between the interior of the country and the Port of Abidjan, required significant repair and reinforcement. This included strengthening the pre-stressed concrete box girders and replacement of the existing bored pile foundations. Replacement piles had to be adjacent to, and no longer than, the existing piles, in order to not compromise the stability of the operational bridge during the works. The underlying geology, however, meant that the pile loads had to be predominantly transferred into the ground through end bearing. Rather than installing a greater number of piles or larger diameter piles, innovative thinking changed the usual mind-set of designing the piles to the prevailing ground conditions, to designing the ground conditions to suit the piles. Jet grouted columns were installed beneath the toes of the new piles to increase the bearing capacity of the ground. This significantly contributed to the sustainability of the project and reduced carbon emissions through saving concrete, steel, plus transportation and disposal of spoil.

Sep 8, 2021

By Albert Neumann, Franz-Werner Gerressen, Giancarlo Santarelli

"Diaphragm walls are known as underground structural elements commonly used for retention systems and permanent foundation walls or elements. In addition they are also quite often used as deep groundwater barriers, named Cut-Off-Walls (COW). Due to the requirements of each particular job site, e.g. the need for carrying high loads or as seepage barriers, there is an increasing industry demand for efficiently cutting into rock. Besides the removal of boulders, cutting through rock, is always the most difficult part of the excavation process of a diaphragm wall or COW.There are a number of influencing factors which have an impact on the rock cutting performance. Besides the influence of the rock characteristics itself, which is not always the same, there are other factors related to equipment, tooling as well as the operating staff. In addition to RQD, the most commonly available rock property found in geotechnical reports is the Unconfined Compressive Strength (UCS) value. There are however some other related properties, such as weathering, bedding, inclination, abrasiveness, etc.,which can have a major impact on the achievable cutting performance. This paper will discuss the various parameters, and how they can be considered for performance estimation. Based on experiences gained on over 100 projects, a performance estimation chart was developed to allow for a better approach to these kinds of projects. This paper also explains the general installation process in as well as some specific features related to specific site conditions. In addition, some job site references will give more detailed information about such type of site conditions and how to deal with them.Keywords: Diaphragm wall, Cut-Off-Wall, Trench Cutter, RockINTRODUCTIONDiaphragm walls are known as underground structural elements commonly used as retention systems for excavation pits, shafts, permanent foundation walls and load bearing elements.It can be anticipated that, with the increasing trend of utilizing more and more underground space to accommodate environmental considerations and urban/suburban development, there will be an increasing requirement for diaphragm wall usage in even more difficult conditions.In addition diaphragm walls can also be used as deep groundwater barriers (Cut-Off-Walls). This market has demonstrated that the demand for these types of walls is reaching ever more difficult soil conditions and greater depths which are surpassing the current industry standards. The trench cutter is the most important tool for performing this type of work."

Jan 1, 2016

By Robert J. Carle

This paper reviews a variety of highway structures which have been built using steel sheet piling as the permanent structural elements of bridge piers, abutments and wingwalls. Those structures built over the past 20 years in Europe include major highway bridges over railroads, highways and waterways in both urban and rural locations. Most highway structures built in the United States using steel sheet piling have been limited to secondary roads in rural locations. The main thrust of this paper is the presentation of various design concepts for highway structures which utilize steel sheet piling. The main purpose is to challenge the profession to move forward from this conceptual presentation and to develop the details necessary to provide safe, cost-effective structures which go well beyond the scope of those being built in the United States today.

Jan 1, 1989

By Laurel E. Blackman

The DFI Project Information Management Systems (PIMS) Committee cooperated with the US Army Corps of Engineers (USACE) to develop a specification for PIMS used on USACE projects. Once completed the Committee developed a more generic version of this specification for general use, which is contained in this document. This first edition has simply removed the USACE-related requirements from the document. The committee will continue to work on this specification to enhance the content and also incorporate recent technological development for these systems. It is the Committee's intention that a second edition will be issued in 2022.

Jan 1, 2021

By John P. Turner, Benjamin J. Turner

"This report describes a research project for evaluating the applicability of the widely accepted 80 percent criterion for elongation of ground anchors to anchors with unbonded lengths exceeding 100 feet. This issue is driven by several recent projects involving ground anchors for landslide stabilization in which a significant percentage of the anchors did not meet the criterion that requires measured elongation during proof load testing of at least 80 percent of the theoretical elastic elongation. The projects involved anchor unbonded lengths in the range of 85 to 220 feet, which is outside the range traditionally used in practice, although anchors of this length are being used more frequently for landslide stabilization. The principal objective of this research is to address whether the widely accepted criterion of 80 percent elongation is applicable for such applications, and whether other factors affect the ability of anchors to meet the criterion.Analytical methods for predicting transfer of load along the length of steel strand due to friction loss are used routinely in the prestressed concrete industry. These analytical expressions provide a rational framework for quantifying changes in load due to friction along the length of a ground anchor in terms of a ‘wobble coefficient’ (K) as defined in Aalami (2004). Values of the wobble coefficient for ground anchors can only be determined by back-calculating from load tests, i.e., fit the value of K to the appropriate analytical expression based on the known test load and measured percent elongation. The analytical basis is first developed and shown to provide a tool for evaluating results of anchor load tests to determine the magnitude of expected elongation as a function of unbonded length. Next, a database of anchor load tests is used to back-calculate values of K for anchors with unbonded lengths in the range typically used in geotechnical applications (< 100 feet). These values of K are then used to calculate expected friction loss for anchors with high unbonded lengths (100 to 250 feet) to evaluate whether the 80 percent criterion is reasonable."

Jan 1, 2017

By Esam Abraham

A 13.6 mile portion of the 500 kV Tehachapi Renewable Transmission Project crosses the mountains of the Angeles National Forest. Access and environmental constraints precluded road development for most transmission tower foundations, tower erection and conductor stringing operations. Because of the access constraints, helicopter-supported micropile foundation construction was used for this steep and environmentally sensitive portion of the project. The general methodologies incorporated on the project represent innovative implementations of micropile design criteria, preconstruction micropile installation and verification testing, on-site geotechnical characterization, micropile and pile cap installation, and proof load testing. Challenges in constructing the 224 foundations for 56 transmission towers provide lessons learned related to transmission lattice steel tower specific design constraints, construction challenges (environmental and geotechnical), and construction schedule.

Jan 1, 2010

By Robert B. Bittner

The new gated dam on the Monongahela River at Braddock, Pennsylvania, was built for the US Army Corps of Engineers using an innovative "In-the-Wef&apos; technology. A key feature of this technology involves construction of the foundations through the water and later mating the completed structure or a shell of the structure to the pre-installed foundation. This paper presents a description of the structure, its foundation, construction sequence and design details required to successfully Implement this technology.

May 11, 2007

By Juhyung Lee

Numerical analyses were performed to analyze the behavior of two different type of suction piles (mono type and group type) under various soil layer conditions (uniform silty clay layer, uniform silty sand layer, and two-layer deposit consisting of clay and sand layers) and lateral loading locations (top, middle, and bottom of the suction pile). According to the results, mono suction pile shows maximum resistance when load is applied on its middle, regardless of the soil layer conditions, while group suction piles varies significantly according to the allowance on head rotation. When head rotation is allowed, the behavior of group type piles become similar to the behavior of mono suction pile. Whereas, when rotation is prevented, resistance is maximized when load is applied on the top head. Moreover, group suction piles show higher efficiency regardless of the ground condition and geological stratum. For further advances, concrete block on the top of group suction piles are suggested as an effective alternative method to prevent partial rotation and maximize ground resistance for group suction piles.

By Ilhan Chang, Ernest Nsabimana, Kiseok Kwak, Juhyung Lee, Young-Hoon Jung

"Numerical analyses were performed to analyze the behavior of two different type of suction piles (mono type and group type) under various soil layer conditions (uniform silty clay layer, uniform silty sand layer, and two-layer deposit consisting of clay and sand layers) and lateral loading locations (top, middle, and bottom of the suction pile). According to the results, mono suction pile shows maximum resistance when load is applied on its middle, regardless of the soil layer conditions, while group suction piles varies significantly according to the allowance on head rotation. When head rotation is allowed, the behavior of group type piles become similar to the behavior of mono suction pile. Whereas, when rotation is prevented, resistance is maximized when load is applied on the top head. Moreover, group suction piles show higher efficiency regardless of the ground condition and geological stratum. For further advances, concrete block on the top of group suction piles are suggested as an effective alternative method to prevent partial rotation and maximize ground resistance for group suction piles.IntroductionWith the development of offshore technology, applications and real site installations of suction piles are increasing significantly nowadays. They are generally used as mooring anchors in various floating structures, marine platforms, and offshore wind turbines. According to its convenience in installation and removal, suction type foundations are becoming good alternatives for deep ocean support systems. The bearing capacity is similar to the bearing behavior of ordinary offshore structures (piles or drilled shafts). The most common use of suction caissons is anchors for catenary mooring lines, where the chain angle at the mudline is close to zero (Randolph, 2002; Sharma, 2004).Recently, it is reported that a huge isolated single suction pile can be replaced by a group of moderatesized suction piles (Randolph et al. 2004). A single monopile is easy to be produced and installed in site. It is expected that monopile foundation is not applicable for deep depths because it has a limitation on penetration according to its huge side skin area (i.e. friction). Moreover, stiffness requirements sometimes render thicker pile wall conditions which are impractical to be produced."

Jan 1, 2017

By Dennis Nottingham

Increased interest in seismic soil liquefaction and preventative soil stabilization sets the stage for improved deep compaction methods using pile driving techniques. In 1971 L.B. Foster Company personnel patented a method of deep compaction using a vibratory pile hammer and pile probe. The technique had some success, but did not produce consistent results and thus found its way to obscurity. Other patents attempted to modify the technique by various probe modifications, but again without measurable improvement from a practical point of view. Solutions to economical deep compaction up to 100-foot depths particularly in saturated granular soils would have a great impact on the construction industry and new bulkhead structures being developed, thus PND was prompted into related research and development. The advent of higher horsepower vibratory hammers, coupled with PND engineers&apos; experiments, observations and measurements, led to an "H" pile probe design which has produced measured soil density improvements up to 250% using SPT "N60" values as a measure. Case histories of two projects involving extensive SPT soil sampling comparative measurements will be discussed along with findings that led to the compaction success. Applications to numerous modern "Open Cell" bulkhead projects will be presented and discussed.

Jan 1, 2004

By Stephan Jefferis

It is my understanding that the Scandinavians have done some fundamental work on durability. I have seen a study published whereby the author, Helen Anderson, comments on the durability of polyurethane grouts and there was -if I am not mistaken- a reference made to another Scandinavian testing institute comparing durability of the polyurethane to cement grout under the same type of circumstances. Circumstances are important so we should actually ask the gentleman to shed some light on this particular method because apparently Scandinavia is the place where durability has been taken very seriously and has been well researched.

Feb 10, 2003

By Jorj O. Osterberg

This paper is for presentation at the 14th Annual Members Conference of the Deep Foundations Institute held at the Hyatt Regency Hotel, Baltimore Maryland on October 10, 1989. This is an introductory presentation of a one hour symposium on the applications of a new testing device. This paper discusses how the device works and its uses. Papers following this describe: - How the cell is constructed and calibrated - Two projects on which the device was used on long driven piles to determine the frictional capacity - A bridge project on which the device was used on an instrumented test drilled shaft and a working drilled shaft

Jan 1, 1989

By Ryan Law

Ground energy systems are being installed in increasing numbers in the United Kingdom. This is particularly true in London where planning regulations require larger scale developments to provide at least 10% of their entire energy demands from renewable sources. A common approach has been to use the groundwater from the Chalk aquifer as a source of energy. This paper explains the potential long and short term sustainability problems with groundwater based systems sited in central London (or any other urbanized area). It also outlines an approach to site testing and numerical modelling to ensure that the system functions well throughout its lifetime. This approach is then applied to a project located in central London.

Jan 1, 2008

By Alexander Scheuermann, Martin D. Larisch, David J. Williams

"Drilled displacement piles (DDP) have been used around the world for decades as foundation elements for structures and embankments. Typically the pile toes are designed to penetrate into stiff or dense soil formations to achieve sufficient base resistance. Recent research at The University of Queensland in Brisbane, Australia has discovered that the in situ stress conditions in stiff to hard clays is directly related to pile installation rates, which in turn are a function of the piling rig capacity and ground conditions. With adequate and constant pile penetration rates in situ stress conditions in the stiff to hard clay are increased by about 40%, resulting in significantly higher pile capacities. If pile penetration rates are too slow the in situ stress conditions are reduced considerably by remoulding and shearing of the clay, potentially causing reduced pile capacities. The paper presents the results of full-scale test piles at a stiff to hard clay site installed using different full-scale piling equipment.INTRODUCTIONDrilled displacement piling (DDP) is a piling technique in which a hollow stem, fitted with a purpose built displacement tool at the bottom, is drilled into the ground. Dissimilar to non-displacement piles, like Continuous Flight Auger (CFA) piles or conventional rotary bored piles drilled with kelly bars, the soil is not excavated during the DDP penetration process, but is displaced laterally and to a lesser extent vertically. The cavity created by the drilling tool is filled with highly workable concrete during the extraction process. The DDP technique is very economical providing high production rates and creating only marginal drill spoil, which has led to its increased global usage during the last decade. The typical DDP installation process is described in Figure 1."

Jan 1, 1900