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By Masanoub R. Fujioka

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

Jan 1, 1986

By Roger A. Archabal, Omar A. Conte, Gustavo Langoni

This international case study focuses on the rigorous geotechnical interaction and results of a soil improvement program utilized to mitigate consolidation settlements of over 1.5 m [5.0 ft]. The extreme settlement results from very deep, nearly normally consolidated clay and the required high floor loading of a new Logistics Park near Bogota, Colombia. The general subsurface conditions consist of very soft clay extending to depths beyond the 50 m [164.0 ft] explored. A required 1.2 m [3.9 ft] thick fill combined with high floor loads resulted in an applied areal load of approximately 7 ton/m2 [1300 psf] (equivalent to about 4.5m [15.0 ft] of fill). Langan recommended performing a test section to validate the initial consolidation settlement calculations and evaluate possible optimization of the prefabricated vertical drain (PVD) spacing and length. The test section sizing was designed to accurately represent the stresses at depth of the future structures. Extreme settlements of over 1.5 m [5.0 ft] in the center and large differential settlements of over 0.6 m [2.0 ft] were measured between the center and corners of the test section over a relatively short test time. Discussion on the methodology, instrumentation, measured results and future optimization are presented. The recommended soil improvement varied from the standard approaches typically utilized in the area. PROJECT LOCATION AND DESCRIPTION The project site is immediately north-northwest of the city of Bogota in the Bogota Valley. The site is bordered with, and has historically been, farming land bordered to the south by the El Rosal-Bogotá highway. The overall site encompasses about 570,000 m2 [141.0 acres] of gross area and about 484,000 m2 [119.6 acres] of net buildable area. The warehouse complex will consist of 10 very large warehouses with footprints ranging from about 15,000 m2 [3.7 acres] to 30,000 m2 [7.4 acres]. The total building area is about 210,000 m2 [51.9 acres] with most of the remaining areas being paved principal drives, truck parking or administrative parking. The topography of the site is relatively flat and close to final grade in roadway areas. However, the warehouse floors will be raised about 1.2 m [3.9 ft] (equivalent to about 2 t/m2 [370 psf] considering engineered fill) to allow for truck docking. In addition, the design floor loads are heavy and estimated to be up to 5 t/m2 [930 psf] and equivalent to about 2.5m [8.2 ft] of fill. Geotechnical conditions at the site are very weak at depths of 50 meters [165 ft] or more, with soft compressible clays comprising the majority of the soil profile. The Bogota Valley is composed in some areas of very deep alluvial deposits. These deposits have been classified as an important challenge and limitation to the development of high/heavy structures such as the project in question for many years (Orozco, 2006). Soft clay deposits have been encountered even beyond depths of 100 meters [328 ft] in some regions of the Bogota Valley (Sanz, 1994). Extreme settlements can be expected if extensive and high permanent loads (above preconsolidation stress levels) are supported in these thick alluvial deposits.

Jan 1, 2018

By A. Garassino

A pile design was performed for a thermal power station in Egypt and more than 4000 piles were to be driven. Technical economical reasons suggested the choice of driven composite LACOR piles designed for very high specific loads. Some uncertainties on the behaviour of the pile soil system suggested to perform a test on an instrumented pile. Scope of the test was to verify the possibility of developping the required bearing capacity within the range of the allowable pile settlements values and the effect of the pile joint enlargement on that portion of skin friction to be developped by the upper pile section.

Jan 1, 1991

By Venda Oliveira P. J., Correia A. A. S., Danisi C. M.

"AbstractA laboratory study has been undertaken to establish common understanding of the creep phenomenon of a Portuguese soft soil chemically stabilised with binders. In order to study the effect of different stress levels on the strength and on the creep behavior of the stabilised soil, oedometer creep tests and unconfined compressive tests were performed at different curing times. Results show that the creep stress level does not influence the unconfined compressive strength. In addition, the creep phenomenon increases the unconfined compressive strength of the treated soil. Two different secondary compression indexes were recognized from the one-dimensional compression curve which increase with an exponential trend with the creep stress level.IntroductionConstruction on soft soils requires a mandatory soil stabilization work to improve mechanical characteristics of the natural soil. Deep mixing method is a worldwide employed ground improvement method, nevertheless the creep phenomenon hasn’t been yet thoroughly analyzed. Most of the published papers have focused on the analysis of the compressibility and the strength of the soil-binder mixtures without considering the creep phenomenon. However, numerical results (Venda Oliveira et al. 2009) have shown that although settlements that occur during the creep stage (namely creep strains) are less in case of treated columns, they are still important especially due to the high loads applied to the stabilised soil. The few published studies about creep behavior of soil-binder mixtures reveal that the stabilization of an organic soil with cement induces a reduction of creep deformations, which is related to the amount of cement used and that the increase of the organic matter of the soil has a negative impact on soil stabilization, further inducing a slight increase in the creep deformations (Venda Oliveira et al. 2012).As part of the current research the effect of different stress levels on the creep behavior of a soft clayey-silt soil was studied. The binder mixture used to enhance the properties of the soil had a specific composition and quantity. Unconfined compressive strength tests (UCS) and UCS creep tests were carried out at pre-set curing times in order to analyze the creep behavior of the soil-binder mixture. In particular five different creep stress levels were studied to understand its influence on the strength and on the compressibility of the stabilised soil. In addition, considerations about the secondary consolidation index are also presented."

Jan 1, 2014

By A. Boominathan

The behaviour of single piles under lateral dynamic loading is very critical and the study is still a current field of research since 1950's. Though many methods have been developed analytically to estimate the dynamic lateral stiffness, very limited dynamic testing on full scale piles were carried out to study the response of piles under lateral dynamic loading. Hence, field lateral dynamic vibration tests are conducted on driven precast concrete square pile of 400mm size and driven cast in-situ concrete piles of 400mm and 500 mm diameter at a petrochemical complexes site at Haldia (India). The results of steady state and free vibrations tests are discussed herein and compared with the response of the piles estimated from PILAY.

Jan 1, 2002

By M. England

Test equipment has been developed to record automatically both the displacement of the pile head and the load applied during a conventional maintained load pile test. Some systems also have, in addition, been fitted with the facility for maintaining the applied load, as set by the operator, at very constant levels. The advantages are both commercial and technical, but a well trained operator has to be in attendance to control the test. Since typical test specifications in the UK require more than 19 hours to complete, it became inevitable that at least one equipment operator remained on site to expedite the test for its duration. Although electronic measurement and data logging of load tests may be more safe than previous direct observation of dial gauges. A single person remaining on a construction site alone is not to be recommended, even if they are just supervising the test. Further development of the testing system produced equipment which will perform the entire test specification as required without operator intervention. To achieve this, full automation is employed. The patented method particularly addresses the safety requirements and by using additional sensors, detects any uncharacteristic behaviour of the pile under test or of the reaction system and the equipment takes appropriate action in a controlled and safe manner. The quality of test data returned from these automated systems is a key element when analysing pile behaviour with models such as CEMSOLVE? and TIMESETTM. These analysis methods often indicate ground disturbance resulting from installation technique and have allowed pile design to be optimised using actual field data rather than theoretical considerations alone. An additional feature is remote access, this allows the data recorded to be transferred and the progress of the test to be viewed from practically any location. This permits experts to view the data 'live' and allows rapid diagnosis of any problems with the expected pile behaviour.

Jan 1, 2002

By Y. C. Han

The advances in seismic design considering soil-structure interaction or soil-pile-structure interaction are described using a substructure approach. The nonlinearity of soil is considered approximately using a boundary zone model with non-reflective interface, and computer programs are available for practical applications. The validation of model is confirmed with dynamic tests on piles in the field, and the results for a single pile are used to compare with the predictions in this study. The liquefaction for sand soil layer can be accounted for, and a case of liquefaction is discussed. Two practical examples are examined, a vacuum tower structure supported on foundation of steel pile group and a table top structure supported on foundation of concrete pile group. To illustrate the effects of soil-pile-structure interaction on the seismic response of vacuum structure, different base conditions are considered, rigid base, i.e. no deformation of the foundation; linear soil-pile system; and nonlinear soil-pile system. The method introduced can be applied to the design of tall buildings, bridges, industrial structures and offshore platforms with soil-pile-structure interaction under seismic or dynamic loads.

Jan 1, 2010

By Michael P. Balducci

Urban deep foundation projects contain unique risks that must be recognized by the parties involved. Common pitfalls must be recognized and avoided or addressed through contractual relations and corresponding insurance coverage. By understanding these pitfalls, examining the risk-apportioning clauses and corresponding insurance obligations, may the parties? desires and expectations be met.

Jan 1, 2008

By Arash Khosravifar

The seismic design of extended pile shafts for the combined effects of dynamic shaking and liquefaction-induced lateral spreading is investigated using nonlinear dynamic finite element analyses (NDA). Results of NDA parameter studies are used to illustrate how inertia and lateral spreading loads combine during shaking. The NDA results are used to evaluate equivalent static analysis (ESA) methods. Implications for design practice are discussed.

Jan 1, 2010

By Z. M. Zhang

Fracture grouting is a particular technique which can be used in soils and rocks with low permeability to increase groutability and penetration rates and to solve some special foundation problems by inducing limited and controlled zones of hydrofracture surrounding the injection source. The present paper describes the basic principles of hydrofracture and its application to grouting in deep foundations, and indicates some recognitions about the mechanisms and effects of fracture grouting.

Jan 1, 2010

By Robert Bachus, Nikolaos Machairasm, Allen Cadden

Data Interchange for Geotechnical and Geoenvironmental Specialists (DIGGS) is a data transfer standard that is gaining widespread acceptance in the geotechnical and geoenvironmental communities. Originally developed using funding from the Federal Highway Administration (FHWA) to efficiently capture data related to geotechnical boring logs, cone penetration test (CPT) soundings, and lab testing results, the data transfer protocol is rapidly gaining traction. It has been shown to have beneficial impacts in other allied areas where disparate parties (i.e., consultants, contractors, vendors, etc.) routinely publish/submit data as part of project deliverables. The historic problem is that many of these submissions use paper copies (i.e., .pdf images) to transmit valuable data for the project… data that may extend beyond the “technical” aspects of the project (e.g., equipment operating conditions, construction production rates, project costs, etc.). These data could be used by multiple parties to assess project performance and safety, as well as to track productivity, etc. Currently, in the limited situations when actual data are compiled and transmitted, the data often are submitted as an author-specific (and often proprietary) software application and must then be re-entered into other software applications (e.g., analysis software, database, etc.) for use beyond simple data collection. An initiative undertaken by the Geo-Institute (G-I) of the American Society of Civil Engineers (ASCE) focuses on exploiting the full potential of DIGGS to geoprofessionals both within and outside of the transportation community. The deep foundations industry represents one community that could benefit significantly from using DIGGS. Data of interest to DFI members include production records, quality assurance information (e.g., verticality and alignment, concrete strength), and, importantly, load test results. When adopting DIGGS, users need not modify how they capture data, but rather will use DIGGS as a vehicle to transfer data to other applications in a standard format where it can be shared, used, stored, and retrieved. This paper and associated presentation will describe DIGGS and demonstrate how DIGGS can be used effectively within the deep foundations community.

Jan 1, 2019

By S. Hardy

The paper describes state of the art non-linear analyses of the pile groups that were employed during the raising of the 133m high triumphal arch which forms the centre piece of the new Wembley stadium in North London. The deformation behaviour of these piles groups was critical during the lifting process, due to the slendemess of the arch structure. The issue was made more critical by the high profile nature of the project. The results of Class A (Lambe (1973)) predictions of the pile group movements are compared with observed displacements and rotations which were accurately measured on site. To illustrate the importance of soil non-linearity on pile group behaviour, comparison is also made with pile group analyses which assume a linear soil stiffness.

Jan 1, 2006

By Lee Sieng Kai

This paper presents the result of the analysis of strain-dependent concrete modulus from full-scale static axial compression load tests conducted on more than 200 instrumented cast-in-place barrettes and bored piles over the past 12 years, covering commonly adopted grades of concrete for heavy foundation construction in Malaysia and Singapore. The concrete modulus values, Ec, analysed were directly back-calculated from the material of the instrumented test piles by means of placing a layer of vibrating wire strain gauges near the pile head region. The best fit curve for back-calculated concrete secant modulus versus measured axial strain follows non-linear behaviour for both categories of test pile samples analysed. The result of the analysis seems to suggest that using average constant modulus value would generally lead to a significant error in load distribution computation, particularly at high stresses region.

Jan 1, 2006

By Q. M. Huang

In 1979 our company undertook the project of infra-structural work of White Swan Lake Hotel, (International class ) Guangzhou. Visit to the site showed that it was situated at the riverside, covering an area of 54,000 M2 with 30,000 M2 of which reclaimed from Pearl River. The material used for reclamation was black sand which was dredged from the nearby riverbed. The sand had the properties of high permeability and very low internal friction. The basement of the building was 6.2 m below ground level and 3 m lower than the riverbed. Apart from the pile foundation, a diaphragm wall was to be constructed prior to the commencement of excavation work for basement. A feasibility study was carried out to determine the method of construction which would maximize utilization of the plants and equipment that were available in the execution of the aforesaid foundation works. This report concerns only the construction of the diaphragm wall and the performance of the plants employed. A detailed delineation of the construction method is herein discussed

Jan 1, 2010

By X. L. Huang

This paper deals with the experimental and theoretic study of the contact pressure beneath the deep foundation of Beijing International Hotel, The experiments have been carried out in project and in model footing 6.6m2. The result of measurements shows the contact pressure at the edge is greater than that at the center. The theoretic analysis on the base of elastic theorey is in good agreement with the test if the proposed assumption used.

Jan 1, 2010

By George G. Goble

In the middle of the nineteenth century, the dynamic formula appeared as a description of pile penetration during impact driving. The simplicity of use of the formula combined with the power of the energy concepts behind the formula caused it to be quickly accepted and integrated into practice. Dynamic formula had been in use for 100 years when the Wave Equation computer programs first appeared. With that long experience it is not surprising that the formula continued to be used and were only slowly abandoned. The Wave Equation offers many advantages over the various formula but it does not offer a clear sense of physical understanding of pile driving that is available with the formula. Large amounts of numbers are generated but often it is difficult or impossible to gain a physical understanding of the results or a feeling for the importance of the various parameters. The question that the Wave Equation user has is, "What will happen if I use a larger drive cap (or change any other item of equipment)?" In this paper, I will attempt to explain pile driving using elementary wave propagation theory. However, the presentation will not depend on any higher mathematics. With the use of wave mechanics, it is possible to explain driving characteristics that cannot be handled with the energy formula.

Jan 1, 1995

By T. J. Snell

Bolnore Village in Haywards Heath, Sussex, England, is a large development covering 8 to 10 hectares and expected to provide 1500 homes in five phases to assist in the continuing demand for new homes in the London area. Part of the development required housing on a relatively shallow slope found to have deep seated failure planes which are fairly prevalent in this part of Sussex. Locally the slope angle was around 20 degrees but more typically the gradient was 6 to 7 degrees. There were significant concerns about slope stability and bearing capacity due to pre-existing shear surfaces and the complex geotechnical profile. There was some evidence of instability in the form of residual shear surfaces and tension cracks. The development required terracing the site with retaining structures up to 5 meters in height, formation of access roads and foundations of new houses. The developer Crest Nicholson adopted a collaborative approach with consulting engineers Powell Tolner and specialist geotechnical contractor Keller Ground Engineering. The solution consisted of a novel combination of contiguous bored piling, ground anchors, and both block work and timbacrib retaining walls to ensure the geotechnical issues were adequately addressed within the time and cost constraints set by the team. The paper describes the geotechnics of the problem together with the design, practical implementation, and site progress achieved

Jan 1, 2006

By James V. Errico

On October 1, 1993 the regulations for assessing and cleaning up contaminated soil and groundwater in the Commonwealth of Massachusetts were revised. These new regulations, known as the Massachusetts Contingency Plan (MCP) 310 CMR 40.0000, were developed to keep routine releases out of the regulatory system and rely on private parties to handle most releases without Department of Environmental Protection (DEP) oversight. An integral part of the new MCP is the Licensed Site Professional (LSP). An LSP is required to handle activities and render opinions once a site enters the MCP. These regulations must be adhered to where ever a release has occurred, including construction sites. A brief overview of the new MCP is given below; see attached MCP Flowchart for graphical summary. Entering the MCP Process A release of oil or hazardous material (OHM) to the soil or groundwater above applicable reportable quantities (RQ's) or reportable concentrations (RC's) will require notification to the DEP and compliance with applicable provisions of the MCP. RQ's and RC's are listed in the MCP (310 CMR 40.1600) for most compounds that are typically encountered. For each compound there are two RC's for soil (S-1 and S-2) and two for groundwater (GW-1 and GW-2). The S-1 and GW-1 RC's apply to sites that are environmentally more sensitive, as a result they are lower than the S-2 and GW-2 RC's.

Jan 1, 1994

By B. Sivarama Sarma, Biswabikash Rout

"Seepage control has to be achieved with plastic concrete cut-off diaphragm walls in dam structures. Materials selected for construction of cut-off walls must be durable, impermeable and have stiffness comparable to the surrounding soil.Plastic concrete provides a feasible and economical solution for construction of durable and impermeable cut off walls for dam structures. Plastic concrete wall should not be understood as a concrete wall with similar mechanical properties of concrete used in buildings, piles and spillways sections. Though it consists of the same materials as those of conventional concrete it has the major differences in end product due to predominant addition of bentonite slurry in the mix with very high water cement ratio. This makes the hardened concrete with very low compressive strength less than 5MPa and high failure deformations after the peak load.This technical paper examines a case study, the typical specifications on demand for construction and the issues corresponding to misunderstanding of the material as a structural grade concrete material. Conclusions were drawn based on a few project site quality data and trial mix experimental data. The anomalies in specifications on demand for construction of curtain wall in a dam structure were removed with modifications.INTRODUCTIONDiaphragm walls which are constructed in trenches made of plastic concrete basically serve the function of seepage control under confined measures. They should have the ability to sustain and undergo large plastic strains as compared to conventional concrete. The three basic mechanical properties of plastic concrete cut-off walls are to have least permeability, minimum strength to retain its shape and ability to undergo large deformations under confined loading conditions. The constituents of plastic concrete are cement, bentonite, coarse and fine aggregates, chemical additives to improve flow of concrete and sometimes to retard the setting time and water."

Jan 1, 2017

By P. Bermingham

A new approach to load testing of high capacity piles is presented. The method is mobile, inexpensive, repeatable and non-destructive allowing for multiple pile testing at a single site. A reaction mass is placed over a pressure chamber situated atop the pile to be tested. The test method is significant in that it can produce linearly increasing forces of high magnitude (over 5.0 MN) with durations of up to 80 milliseconds. This represents pulse durations an order of magnitude longer than achieved using a drop hammer. The accelerations the pile undergoes are less than one g, (conventional dynamic methods = 50 to 100 g). These effects combine to produce pile behaviour no longer dominated by the action of stress wave, instead the pile is under high levels of stress through its length during the force input. This is representative of the situation when static loads are applied, thus the method may be considered quasi-static. Further advances introduced with this method are that pile deflection and transmitted force are measured directly by means of a laser beam and load cell. This allows accurate correlation of event load displacement histories without the error associated with zero shift (acceleration integration) or non-homogeneous materials (strain measurement). The load displacement histories emulate those obtained for static load testing.

Jan 1, 1989