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By K. Rambha Devi

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

Jan 1, 1996

By 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 Vincent Joannes, Marine Lasne, Luca Brenelli, Colin Serridge, Inge van Baardwijk, Martin Stanley, Anthony Fisher, Mary Ellen Bruce, Tony Suckling, Pedro Avellanosa

"Abstract The European Federation of Foundation Contractors (EFFC) and Deep Foundations Institute (DFI) developed a sector-specific carbon accounting methodology and associated “carbon calculator” for foundations and geotechnical works. The EFFC-DFI Carbon Calculator is believed to be one of the construction industry’s first collaboratively produced carbon calculator tools for European and international countries based on verifiable and standardized data. It is intended that the tool be adopted internationally and become the open-source industry standard for ground works. A detailed methodological guide is provided with the calculator (Lemaignan and Wilmotte, 2013). This guide explains the background of the standards, accounting methodologies, emission sources and factors that were used as the bases for the tool development and includes detailed guidance on use of the calculator.Drivers for DevelopmentFoundation contractors anticipate project cost and carbon emissions will become inextricably linked in response to the climbing price of fossil fuels and carbon intensive materials as resources become scarce. Low carbon solutions will therefore become more competitive options. Also with high profile construction projects having low carbon/carbon neutrality as requirements, sustainability in the foundations industry also becomes a market issue.This carbon calculator will be used to lead the industry and shape the expectations of commissioning organisations by providing insight into the carbon cost of their projects. Commissioning organizations are encouraged to be aware of the carbon impact of projects and to also facilitate a fair and accurate way of comparing footprints to provide a level playing field for foundation contractors."

Jan 1, 2014

By Donald A. Bruce

Various types of contemporary Deep Mixing Method (DMM) techniques have been used in the United States since 1986. Such techniques owe their origins to Japanese and Scandinavian developments, which began almost three decades ago. The growing demands of urban infrastructure development and rehabilitation have created a very active and rapidly expanding market demand in the United States especially since the early 1990s, and there is a clear need for a new and fundamental review of the surprisingly large number of DMM techniques that are being used domestically, or are available in other parts of the world. Following a summary tracing the historical development of DMM, and a generic classification of applications, the paper provides a review of each of the many different proprietary methods, which the authors have identified during preparation of an international survey funded by the Federal Highway Administration (FHWA). Data are also provided on commercial aspects of the various DMM techniques worldwide.

Jan 1, 1998

By Braja M. Das

Laboratory model test results for the ultimate uplift capacity of square and circular foundations in saturated clay (ø=0) have been presented. The results of the present model tests for square foundations have been compared with the previously published laboratory model tests results on circular foundations. Based on the comparison, it appears that the critical embedment ratio of square and circular foundations increases from about 3 for soft clays to about 7 for medium to stiff clays. By using the experimental results, an empirical procedure has been suggested for determination of the ultimate uplift capacity of belled pier foundations in saturated clay.

Jan 1, 1987

By Z. Q. Zhou

It is the first worke in design of pile foundation to determine the carring capacity of single pile, and a static loading on site is considered to be the lost derect and reliable way. All values P and settlements S induced can be plotted as a broken-line. Since soil is a kind of elasto-plastic and cohesive material, the increasing of settlements is generally greater than that of loads. Different value Pu nay be given by different tester on his P-S diagram, because of erroys in the test and complicated, characteristics of soil. The analytical method of exponential equation shown in this paper derives a specified solution. After using an exponential curve to regress values of loads P and corresponding settlements S from on-site test, coeficients A and B of exponential equation can be obtained. With this curve an ultimate carrying capacity of single pile can be determined. The resistant forces of pile shaft and pile tip can also be defined by the tangent of the calculated knee point, as it is called (tangent method). At last, an example is given to show how the ultimate carrying capacity of f 500mm bored pile is obtained with this method for a project in Kunming.

Jan 1, 2010

By Ali Porbaha

In today's fast-track construction environment, owners are searching for non-conventional technologies to build their projects faster and safer while maintaining traffic flow during construction. To that end designers and contractors are providing solutions that incorporate many unique features to expedite construction processes. In addition to timely delivery of the finished highway products, there is an increasing interest in making the initial investment in applying innovative technologies and thereby minimizing costly maintenance of highway projects. Accordingly, the aim of this paper (along with the accompanying paper) is to examine innovative technologies, developed mostly in Europe, that accelerate construction of highway, runway and railway embankment foundations. For each technology, a basic concept, installation technique(s), and design considerations are discussed, along with the case history of a real-world project. The Geotextile Encased Columns (GEC), AuGeo, and Continuous Flight Auger (CFA) are presented in Part I. Deep Mixing (DM), Mass stabilization, Cut-Mix-Injection (FMI), and Combined soil Stabilization with Vertical columns (CSV) technologies are discussed in Part II.

Jan 1, 2002

By D. A. Greenwood

Dr David Greenwood opened the first technical session of the conference by highlighting the diverse nature of the papers in this session but drawing attention to the common theme that each solved a particular problem. PAPER 1.1 Tony Elliott introduced his paper on deep mix-in-place soil/cement stabilisation by stressing its simplicity. The engineering solution adopted at Elland was detailed in his paper and had formed the key to success of the project. The process itself is not widely used or known in the UK, although it has the potential to achieve significant benefits, subject to proper engineering control being exercised. It was explained that although the concept was not new, development of the technique for soil modification was relatively recent. The alternatives to mechanical mixing are injection, which is very dependent on soil type, site geometry, etc, and jet grouting; both processes are soil-responsive, and not easily monitored or programmed, difficulties which can largely be overcome by mixing. To achieve this at depths to say 30m requires high-powered, high torque machines and has resulted in significant equipment development.

Jan 1, 1991

By Jorj O. Osterberg

The Osterberg (O-Cell) Method makes it possible to separate the side shear resistance (skin friction) from end bearing. The O-Cell is placed on or near the bottom of a drilled shaft and after the concrete is poured and cured, an equal upward and downward pressure is applied. From the test, the load-upward deflection curve in side shear and the load-downward deflection curve in end bearing are drawn. Typical curves are shown where the ultimate load in side-shear is reached and where the ultimate load in end bearing is reached. Several examples of tests in which the test load reached ultimate loads far in excess of what was expected are shown. The side shear in rock sockets is shown to be much larger than generally estimated. Examples are given of where side shear is smaller than expected and the reasons discussed. Disturbance of the sides of drilled holes due to poor construction techniques and ways to avoid these conditions are considered. Examples of bottom hole disturbance are given and ways to prevent the disturbance are discussed. A graph showing the actual measured capacity of drilled shafts compared to the estimated capacity as a function of the hardness and strength of the soil or rock is presented.

Jan 1, 1999

By Frank Haehnig, Kurt Kogler

"With a height of 200 m, a crown width of 626 m and a concrete volume of 1.6 million m³, the Kölnbrein Dam in the upper Malta valley in Carinthia / Austria is the largest concrete dam in Austria. Boasting a storage capacity of 200 million m³ with a received water load of 54 MN, this is one of the strongest arch dams in the world.During its construction from 1974 to 1977, the dam was equipped with a comprehensive monitoring system capable of comparing developing deformations and stresses with the design values.With a planned reservoir level of 1,900 m a.s.l. the dam saw the reservoir level of 1,860 m a.s.l. breached in the year 1978. This led to extremely high seepage losses of up to 200 ltr/sec and a rise in the foundation water pressure up to 100% of the dam’s height. These observations were caused by the development of horizontal cracks in the area of the middle dam blocks, between the lowest inspection walkway and the waterside.As a consequence, power plant operations had to significantly be reduced and a number of additional measures were carried out – though these did not lead to the desired sealings.The developer subsequently decided that the dam should undergo a general rehabilitation from 1998 to 1994 in accordance with a concept developed by Professor Lombardi. This concept involved erecting a 50 m high support structure with a concrete volume of 500,000 m³ on the airside of the dam, along with the addition of neoprene bearings to transfer 1.2 million tons of the horizontal load. These measures were able to reduce the deformations in the dam enough so that mostly load-bearing injections into the cracks in the dam’s concrete could successfully be carried out by way of targeted grouting measures using injection resin (RODUR) specifically developed for this purpose.In the years 1998 - 1994, a total of 130,000 m of grouting, monitoring and control drillings were executed, and around 200,000 kg of synthetic resin was injected into the cracks in the dam’s concrete.These measures have ensured the dam‘s uninterrupted operation since 1994. A number of small re- injections were again carried out on the contact surface in the years 2011 and 2012."

Jan 1, 2016

By William E. Lardner

Interlocking caisson walls developed from conventional "soldier pile and lagging" shoring. In the latter, the soldier piles receive directly most of the soil load. Natural arches form in the soil behind the shoring; the lagging supports little more than the segment of soil inside the arch. Fig. 1: A typical layout of a lagged wall [ ] Fig. 2: A typical layout of an interlocking caisson wall [ ]

Jan 1, 1987

By Sam X. Yao

The underwater concrete technology has historically evolved largely through a trial-and-error process of constructing marine works. Many outstanding examples exist of high quality concrete placed underwater. However, failures also occurred and led to excessive cost and/or schedule overruns. These failures were largely due to improper concrete mix design or improper placement. The problems may have occurred because proper underwater concrete construction techniques and experience have not been widely disseminated. This section focuses on technical issues of underwater concrete mix design, concrete production and placement, and quality control.

Jan 1, 2013

By A. Lyndon

Combined loading tests are described to three 1.2m diameter cast-in-place bored piles, 12m long, formed through cohesionless material into stiff sandy clay. The maximum loading conditions imposed at the pile head were 2400 kN vertical, 160 kN lateral and 3120 kNm in bending, corresponding to twice the working load. Settlements, deflections and rotations of the piles were measured during the tests. An interesting finding which the test results suggest is that, in the short term, vertical movement had apparently no marked effect on lateral performance for piles working at design loadings.

Jan 1, 1989

By Lin Daoyi

In this paper, we have adopted the high pressure jet-grouting curtains to seal the sea-water, and to consolidate the wall of the well for deep foundation diteh, make a pladge of building and construction of deep foundation was primarily on progress without water. This paper, we have been given a test for pumping water under mainly the circumtances of sealing condition and to report in advance the capacity of seawater seeping into the gam curtains in the process of building and construction of deep foundation.

Jan 1, 1991

By Y. G. Qin

In this article an experimental study of axial bearing capacity of half-closed steel pipe pile installed at BKSH dock is presented. In comparison with open and closed end piles, half-closed end pile is considered to have high bearing capacity and good penetration, that is, it not only has a capacity as twice as the same size open end steel pipe pile, but also has blow counts as half as the same size closed end steel pipe pile. It is economic to use half-closed end pile in soft ground without a deep deposit of thick stiff clay. This article also describes a large scale model pile test and preliminarily analyses mechanism of improvement of bearing capacity of half-closed end pile with emphasis on effect of squeezed soil on side friction; an empirical approach is presented in which side friction is related to density of squeezed soil and which is useful for reasonably chosing side friction of different types of piles in design of foundarion.

Jan 1, 2010

By Takashi Saito

Since early 1970?s skirt suction foundations (skirted foundation / bucket foundation) have been used as support for large fixed substructures or anchors for floating structures in offshore hydrocarbon development projects. In recent years skirt suction foundations are recognized as one of the solutions in foundations applicable to bridge substructures installed in waters, because skirt foundations have a wide variety of functions such as control of settlement during service life, less impact to environments during operation at installation site. This paper introduces general features of skirt suction foundations, and then discusses design practice of them for the application to bridge substructures, with reference to experiments in both laboratory and field.

Jan 1, 2013

By Charles L. Guild

I will add a few facts about the use and development of the Osterberg Test Load Cell and my association with Jorj. I first met Jorj in 1965 when the Guild Construction Co. drove 12" diameter cast-in-place shell piles for him at the Marquette Cement Co. in Nashville, Tennessee. When I met Jorj at the DFI Trustee's meeting in 1985 at Longboat Key, Florida, he showed me a sketch of his idea about using a test cell at the bottom of a caisson to test the end bearing and side friction on a caisson. He had made a successful trial test in Case International's equipment yard and wondered whether a similar device could be made for a driven pile. At first I was skeptical that it could be done but after thinking about it overnight I told him I felt it was feasible and we would do some work on it. At that time, there was a large bridge job going out for bid in Rhode Island using 14" square prestressed concrete piles'. Based on a record of the Guild Construction Co. Inc. driving over 3,000,000 feet of piling on work for the State of R.I., we felt we would have an excellent chance to be allowed to use them so we designed, detailed and fabricated three for 14" square prestressed concrete piles. As things worked out, we did not test them on this job and have not to date.

Jan 1, 1989

By Howard Roscoe

Linking Ashford International Station to the new Channel Tunnel Rail Link required over 5000 rotary bored and CFA (continuous flight auger) piles to form tunnel walls and viaduct foundations and to support overbridges and trackside barriers.. Much of the work was carried out close to the existing railway infrastructure. Plunged columns were used to maintain traffic flows over the tunnel site during construction. The results of an extensive programme of vertical and lateral load tests on bored and CFA piles in heavily overconsolidated Weald Clay are compared to illustrate the relative importance of stress relief and of prolonged exposure to bentonite. The completion on schedule of this major piling and ground engineering contract (value £30 million) demonstrates that collaborative working in partnership produced cost effective solutions to a series of challenging technical and logistical problems.

Jan 1, 2002

By Karen J. Dawson, Francisco Johnson

"Pressure-grouted high strength helical displacement piles are a recently developed pile type that can be useful in conditions where noise or vibrations must be low or where access or clearance is limited. However, there is no information in the literature that can be used to estimate the soil resistance of these piles or production rates. To fill this information need, this paper presents a New Jersey installation case history and the results of static axial and lateral load tests on both pressure-grouted and ungrouted high strength helical piles at the case history site and trial installation locations in New Jersey and Washington State. Piles between 25 and 50 feet long comprised of steel shaft diameters of 4.5, 5.5, and 7 inches with equivalent grout column diameters ranging from 12 to 22 inches were tested. Lateral loads of up to 100 kips and axial compression loads of up to 700 kips were applied. The results of the load tests are compared to predictions of lateral deformation and axial resistance.INTRODUCTIONHelical piles have long been recognized as a useful foundation type in situations where noise and vibrations must be limited, or where there are access or clearance restrictions. Relatively well-documented design methods and torque to capacity correlations have been developed for the most commonly used helical piles, which are relatively small (typically shafts of 6 inches or less) with corresponding low load carrying resistance.With the increased need to construct in congested urban environments, there is incentive to develop helical piles with higher axial resistance. Seismic and other loading conditions also require lateral resistance, which is low for the typically small helical pile shafts. One method of increasing the soil resistance, both axially and laterally and at relatively low cost, is to place grout around the shaft. Injecting the grout under pressure through the hollow helical pipe section and out a grout port or ports located near the toe of the pile has the potential to increase the pile resistance significantly above that which can be achieve by gravity grouting. Not only does the pressurized grout push out against the surrounding soil, but the rotating helix helps to distribute the grout laterally. Unfortunately, little information is available in the literature to help designers estimate the resistance of grouted helical piles in general and none is available regarding pressuregrouted helical piles."

Jan 1, 2016

Jan 1, 2003