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By Kul Bhushan

This paper presents the results of lateral load tests on 0.61-m to 1.27-m (24 to 50-inch) diameter drilled and cast-in-place piers in San Diego area residual/formational soils. The test piers were installed and tested in the following soils: Decomposed Granitic Rock (Ktd), Stadium Conglomerate (Tst), and Friars Formation (Tf). Lateral loads of up to 845 KN (190 kip) were applied to the piers in residual granitic soils, and loads up to 1780 KN (400 kip) were applied to the piers in Stadium Conglomerate and Friars Formation. The tests were conducted by jacking against adjacent piers and monitoring the lateral load and lateral deflection at the ground line. Test results indicate that ultimate lateral pile capacities of up to 1800 KN (400 kip) can be obtained for 0.61 m (24-inch) drilled piers with penetration of 3 to 6 m (10 to 20 ft) in the residual/formational soils tested. Lateral load analyses using p-y curves for very dense sand significantly overestimate the observed lateral deflections. For lateral load analyses using dense sand p-y curves, p-multipliers that increase the lateral soil stiffness (p-y curves) by 2 to 8 times are required to match the load-deflection behavior measured in the test piles. When applied to the dense sand p-y curves, the p-multipliers provide a more accurate prediction of load-deflection behavior in the residual/formational soils, and can result in shorter required pier penetration and significant savings in foundation cost.

Jan 1, 2002

By Li Keqiang

This paper discusses the pile foundation of tall buildings in Shenzhen region. For 156 constructed tall buildings exceeding 18 storeys, about 86. 5 per cent of the sum. The two main types of foundation used are the semi?machine?bored/slurry drilled cast?in?situ pile and the excavation pile (hand ?dug caisson). The engineering geologiical condition in Shenzhen was analysed. In general, the bed rock level is not too deep. It belongs to hard rock, but the geologic structure is more complex and the tectonic fissures is plenty. According to experiences of the researches, tests, designs and constructions of pile foundation, we present the basic design principle of pile foundations for tall buildings as follows; (1) pile strength control to select the pile type and to choice the cross sectional dimen­sions, must be in compliance with the strength of the pile. (2) bearing stratum strongly weathered, moderartely weathered and slightly weathered rock may be used as the bearing stratum. (3) bearing pile bored /drilled cast-in-situ pile designed as an end bearing pile. (4) friction pile precast concrete pile, prestressed concrete tubular pile and driven cast-in-situ pile designe as a friction pile. In case, pile design is in compliance with these principles, it may be safe, economical and reasonable.

Jan 1, 1991

By Raymond J. Castelli

The paper provides a general overview of the numerous types of earth retaining systems currently available, and organizes these various systems by several classification methods. These classifications can be used as a guide in identifying the appropriate type wall or walls for any specific project application. As a further aid in sorting through the numerous wall alternatives for a specific design or construction project application, the paper suggests a systematic approach for wall selection, and presents helpful charts summarizing the general advantages and disadvantages, and typical limitations for the currently available wall systems.

Jan 1, 2003

By Almer E. C. van der Stoel

"Abstract This paper deals with assessing the bearing capacity of existing wood pile foundations. With a wide range of restoration projects being performed in the Netherlands, on many locations deep excavations need to be constructed next to existing, many times listed buildings. The building are founded on piles that are often centuries old, so a close evaluation of the remaining bearing capacity, combined with and assessment of the influence of the excavation is in place.After giving an introduction on Dutch pile foundations, a methodology is described to assess the bearing capacity. Aspects as physical foundation investigation, determination of the current bearing capacity and a calculation of the bearing capacity in the new situation are discussed. The results of both analytical and Plaxis calculations are outlined, focussing on how to practically use this approach in renovation projects. Finally, cases studies of the successful application of this approach in major renovation projects in Amsterdam, such as the Conservatorium Hotel and the New Rijksmuseum are used to illustrate the successful application of this approach.A Short Dutch Pile Foundation History (based on Van der Stoel, 2001)The first houses built in Amsterdam, in the 12th century, were very light constructions of timber without foundations. Because of the soft peat layers found in Amsterdam, the houses there suffered from damage due to settlement. In the 13th century, castles and churches were increasingly built of bricks, which made it necessary to provide support for bigger loads. Under the wall of the construction a trench was dug, and this was filled on either side by alder fascines. Between the fascines small wood piles were driven (by hand) on which another series of fascines was put. On top of this construction, were placed oak slabs on which the bricks were then laid. From that moment on, a problem was caused by the decay of wood foundation elements in the humid soil. In 1503 a law was introduced forbidding building foundations on public streets without permission of the Building Inspection (to keep the fronts of the buildings in a straight line). In 1528 a law requiring permission from the local authorities for all building activities replaced this law. In this period developments started which led to the use of the type of foundation that can be considered the mother of the current “typical” Dutch pile foundation. The piles used in this period were shaft- bearing piles about 5 to 7 meters long. The mostly pine piles were driven between oak beams, which were placed on either sides of a trench, after which other oak beams were laid across at regular spaces: the so called “pile bent” pile foundation (Figure 1)."

Jan 1, 2014

By Shaw-Shong Liew

This paper presents the processes of investigation, analysis, design, construction and monitoring of soil nail stabilisation work to facilitate a 14.5 m deep excavation at an uncontrolled fill ground. An extensive instrumentation programme had been implemented to monitor the performance of the stabilisation solution, to provide validation for the designed nail resistance and groundwater variation. From the monitoring results, it was proved that the soil nail stabilisation technique is effective for loose saturated fill provided that substantial care is taken during implementation. Construction difficulties, solutions to overcome the problems and lessons learned will be discussed in the paper.

Jan 1, 2006

By Martin van Staveren

In today's rapid changing construction world, the business pressures on piling and deep foundations reach sky-high levels. Ever increasing complexity of construction projects do severely contribute to these business pressures. Projects are often constructed in densely populated areas and located close to vulnerable buildings and infrastructure. The inherent uncertainty of ground conditions plays a dominating role in these foundation projects. Effective risk management is a key success factor for profitable and sustainable operations of piling and deep foundations. It starts with a fundamental requirement to be aware of risks. Next the different risk perspectives of all stakeholders in any foundation project have to be acknowledged. A simple and structured risk management approach is introduced, to demonstrate that effective risk management is not necessarily that complicated. A major element is the contractual allocation of risks, as a result from differing ground conditions. It is based on the so-called Geotechnical Baseline Report (GBR). The main objective of the GBR is to provide a clear contractual arrangement for the allocation of risks, arising from differing site conditions. The benefits of explicit risk management in general and contractual risk allocation in particular are illustrated with an example and experiences. The presented structured risk management approach, including contractual risk allocation, is still rather new. It proves to be promising for cost-effective risk control of piling and deep foundation projects, anywhere in the world.

Jan 1, 2006

By Claudio Olalla

This paper relates to the foundation of a steel structure located at the San Martin de la Vega (Madrid) amusement park. The structure has more than 100 supports with various loading conditions, including important horizontal and uplift forces. Additionally, the settlement tolerances are very strict. A massive gypsum formation with interbedded clay layers and random solution great voids at various levels constitute the soil. The foundation design has been conditioned large enough these difficulties (load conditions and soil problems). The piling machine used was powerful to drill through the soft rock (UCS up to 11Mpa). The integrity of each pile had to be guaranteed by continuous recording of drilling and concrete pouring parameters. In order to fulfil all those conditions, a STARSOL type-piling rig was used. More than 4500 meters of piles were performed. The diameters of the piles were 450 and 550-mm and their depths varies from 6 to 23 meters. All piles were reinforced over their full length.

Jan 1, 2002

By Haijian Shi, Drew Pizzo

This article focuses on the appropriate application of subsurface investigation methods for transmission structures, which are typically designed to resist lateral rather than vertical loads. Currently, the three methods used most often for the subsurface investigation of transmission structures in the field are the Standard Penetration Test (SPT), the Cone Penetration Test (CPT), and the Flat Dilatometer Test (DMT). Each of these methods has advantages and disadvantages, and each is more applicable to some scenarios than to others. To gain a better understanding of these test methods and the implications of using them for various kinds of applications, a comparison study was conducted in the field in Maryland, for three boring locations. Each boring location was explored using each of the three tests as stated. The results of the tests and lessons learned are presented and compared, and these comparisons show that the three test methods agree on the majority of the findings. The results from each test method were also used to derive key parameters such as the soil friction angle for given foundation designs considered in order to establish a clear basis for comparison. Recommendations for performing transmission structure subsurface investigations are made in order to optimize the use of each method and thereby optimizing subsequent foundation designs. INTRODUCTION For overhead transmission structures, the most important structural requirement for determining the foundation design differs from the requirement for other structures such as buildings and bridges in accord with the conditions the transmission structures will need to withstand. In addition to the ability to bear a given vertical load consistent with its use, the foundation must bear lateral loads arising from wind and other weather conditions. The foundation types used most often for overhead transmission monopole structures include concrete drilled pier, vibratory caisson, and direct embedment. In order to determine an appropriate and even an optimum foundation design for any given set of conditions, an appropriate subsurface investigation method or approach is needed. Currently, the standard penetration test (SPT), the cone penetration test (CPT), and the flat dilatometer test (DMT) are the three most commonly used subsurface investigation methods.

Jan 1, 2018

By Alan J. Lutenegger

Some years ago, a method was developed to incorporate a grout column around square-shaft helical screw-piles and anchors to increase shaft buckling resistance under compression loading. An additional benefit of this grouted shaft is to increase the load capacity in both compression and tension, depending on the geometry of the lead helical section and the soil conditions. Because of the unique construction procedure, the contribution of the shaft to the total capacity has largely been unknown. The behavior of grouted shaft helical anchors in clay was investigated by performing full-scale axial uplift (tension) load tests on a series of anchors installed at the University of Massachusetts Geotechnical Test Site. In order to isolate the contribution of the grouted shaft to the total load capacity, anchors were installed with a wooden dowel connection between the lead helical section and extension sections on three of the four anchors so that only the shaft resistance would be measured during the load tests. The grouted shafts ranged in length from 10 to 30 ft (3 to 9 m). Initial tests were performed approximately 5½ months after installation. Nearly four years after the initial tests were performed, the tests were repeated to evaluate any significant change in capacity with time and/or repeat testing (preshearing). The soil conditions at the site are presented along with the load-displacement curves for both the initial and repeat teats and a discussion of the analysis of the results. Repeat load tests showed an increase in capacity from the initial testing, however the percent increase was not the same for all depths. The results demonstrate that considerable shaft resistance can be developed in clays from the grouted shafts as might be expected. Depending on the L/D ratio of the shaft and the contribution of the lead helical section, at working loads the shaft capacity can dominate the behavior.

Jan 1, 2011

By Mario Terceros H., Bengt H. Fellenius

"ABSTRACTFour strain-gage instrumented bored piles were constructed in a sedimentary, dense to very dense, fine to medium sand in Santa Cruz, Bolivia. Two of the test piles were the normally used bored pile constructed with bentonite slurry and two piles were Bauer Full Displacement Pile (FDP). One of each pair was equipped with the Expander Body, an inflatable steel cylinder that on pressure-grouting provides an enlarged pile toe. Head-down static loading test were performed on three of the piles and a bidirectional test was performed on the fourth pile, a standard pile with Expander Body and a bidirectional cell placed immediately above the EB. The latter pile was tested in 3 phases. First by activating the cell, second, by a head-down test, and, third, by a repeat bidirectional cell test. The static loading tests proved the shaft resistance of the FDP pile to be about twice that of the standard bored pile and that the Expander Body more than doubled the toe stiffness. The strain-gage records showed that the standard bored piles had multiple bulges and neckings, which affected the evaluation of the axial stiffness and load distribution of the piles. The testing programme was used for a prediction event with 60 persons, ahead of the tests, submitting predictions of the load-movement curves for the test piles and also a capacity appraised from the curves.1. INTRODUCTIONOn April 23 - 26, 2013, the First International Conference and Seminar on Deep Foundations was held in Santa Cruz, Bolivia under the auspices of INCOTEC SRL, the UAGRM University, and the Bolivian Association of Civil Engineers and Chamber of Construction. To coincide with the conference, a research study on construction and static and dynamic testing of four instrumented bored piles was undertaken. To ""add spice"" to the conference, a prediction event was organized on the test programme. This paper presents the soil conditions at the site, the type and construction of the test piles, the outcome of the prediction event, and the results of the static tests.2. SOIL CONDITIONSGeotechnical studies comprising SPT and CPT tests with routine laboratory analysis were performed on recovered soil samples. Three SPT boreholes were put down at three of the locations of Pile TP1, TP2, and TP3, at 5.0 m distance from each other. The SPT procedure consisted of manual hoisting of the weight by three crew members pulling on ropes over a pulley supported by a tripod and letting the weight fall by gravity. The groundwater table lies at 3.5 m depth.Figure 1 shows diagrams of the SPT N-indices and the distribution of water content in the three boreholes. The SPT-indices show the soil density to be compact. The average water content is about 15 %, plus-minus a few percent."

Jan 1, 2014

By K. Englehardt

J BERESFORD introduced the subject of the paper which is the use of polymeric slurries to support the sides of diaphragm wall and bored pile excavations during construction. In the opinion of the authors the use of a suitable polymeric fluid offers financial and technical advantages compared with traditional bentonite based slurries. Under quiescent conditions a support slurry must have the following properties. - sufficient viscosity to support the sides of the excavation, to prevent infiltration into soils and to hold loose soil particles in suspension. - when agitated it should thin quickly to assist pumping transfer and cleaning and allow free passage of the grab or drill. - viscosity should be low enough during concreting to facilitate placement but high enough to prevent contamination of the concrete.

Jan 1, 1991

By Derrick Dasenbrock

Two DFI committees independently organized two complimentary panel sessions for the recent American Society of Civil Engineers' (ASCE) Geo- Risk 2023 "Advances in Theory and Innovation in Practice" Conference in Arlington, Virginia, July 23-26. The Geo- Institute (GI) specialty conference welcomed more than 200 professionals and students interested in risk from around the world to the Washington, D.C., area for three full days of plenary keynote lectures, papers and no-paper sessions. The GI Risk Assessment and Management Technical Committee organized the event, which is the third in a series planned on a 6-year cycle. The previous two events were in 2011 in Atlanta and 2017 in Denver.

Sep 1, 2023

By Alfred H. Brand

New York City contains extensive deep deposits of glacial lake varved silt and clay, often overlain by organic soil. An 18 story building was proposed for Manhattan's upper East Side in one such area where bedrock is approximately 200 ft deep. Various pile and caisson alternatives were considered extending through the glacial lake soil to rock, but all proved beyond the project budget. Laboratory testing showed that the glacial lake deposits were preconsolidated. A test pile program using auger cast piles bearing in the glacial lake deposits proved that such piles could safely carry a load of 60 tons per unit. The auger cast pile scheme was estimated to be more economical than a deep pile alternative. A further benefit was that the vibration-free pile installation procedure posed less risk to adjacent structures which had been founded at shallow depth in fill above organic deposits and were stressed and cracked due to prior settlement. The project was designed with the anticipation that the glacial soils beneath the tips of the piles would produce a building settlement of 1 to 2 inches. The building was constructed in 2001 and 2002. It has been completed and is now occupied. Settlement data show that the building is performing as predicted. The auger cast pile scheme founded in a compressible stratum has proven to be successful and is a very unusual foundation alternative.

Jan 1, 2003

By Anne Lemnitzer

Full-Scale cyclic field testing was performed on a 3x3 pile group consisting of nine cast-in-drilled-hole (CIDH) reinforced concrete shafts and a comparable single-shaft in order to investigate group interaction effects. Both specimens were constructed with pile diameters of d = 0.61m (2 ft), fixed head boundary conditions, and placed in stiff clayey soil at a test site near the LAX Airport in Southern California. Internal instrumentation was installed in the single pile as well as in three piles within the pile group to obtain pile curvatures. External instrumentation controlled the lateral displacement of the specimens. A combination of experimentally and analytically obtained p-y curves for the single pile was used to simulate results for piles located in the group when field data were not available. All test specimens were tested to structural failure and excavated after test completion to investigate pile damage and plastic hinge formations. Calculated group interaction factors ranged between 1.0 at very small displacement levels of <2.5 mm (0.1 in), 0.8 at the initiation of the pile-soil-pile interaction, i.e. between 4 mm - 15 mm (0.16-0.6 in), and increased towards 0.9 near structural failure (displacement >25 mm or 1 in). A literature set of p-multipliers was found to reproduce an accurate fit to the available load displacement test data from the group.

Jan 1, 2010

By J. C. W. M. de Wit

An excavation, within which a tunnel is sunk as a part of the Centraal Station underground station (platform section) of the Noord/Zuidlijn (&apos;North/South Line&apos;), is to be created beneath the Amsterdam Centraal (&apos;Amsterdam Central&apos;) station. The section beneath Amsterdam Centraal Station is characterised by the application of a particular technology in the form of, inter alia, the so-called &apos;sandwich wall&apos;. This is a composite wall consisting of two rows of Tubex piles with a body of jetgrout columns in-between. This wall acts both as an excavation support wall and also provides vertical bearing. The installation of the wall, including both Tubex piles and jetgrout columns, within these specific conditions (limited height, sensitive historical building), within the design requirements set in terms of construction tolerance and water and soil retention, may be regarded as being a pioneering achievement. The environmental constraints are that the trains should continue to run, the inconvenience to passengers should be kept to a minimum and the historic station should not suffer any damage. Because of the complexity of the working conditions, the project is being overseen by a steering group of experts in the specified construction processes. In order to manage the project risks, jet grouting trials were initially carried out, in order to highlight and control execution problems; the practicability of the design is then tested. Work commenced on the sandwich wall in 2003, when the wooden piles were extracted at the locations where the sandwich wall was to be constructed; in 2004, the steel Tubex piles for the southern wall sections were installed. From May 2005, the construction of the sandwich wall got under way; in addition to the described process supervision, an extensive measuring programme was established, so that the process could be adjusted as necessary and the quality of the finished product determined. This applied to both individual columns and for the end product, the sandwich wall. The measurement results were processed for each column, interpreted and the effect on the work still to be conducted was assessed for each future column. Preventative and corrective measures were, if necessary, taken in order to control or counteract the measured defect. In addition to the process-oriented and qualitative measurements, various independent measurement systems at the station building served as a further control in order to prevent damage to the building.

Jan 1, 2006

By Leonardo Massone

The p-y method is one of the most popular methods in pile design and has been calibrated for various boundary conditions using numerical and experimental studies during recent years. Most studies on reinforced concrete (RC) piles have included the impact of flexural nonlinearity, (e.g. nonlinear moment?curvature relations) but not considered associated pile shear deformations when deriving p-y curves from field data. Common p-y curves may be better applicable for piles with flexure dominated failures (e.g. piles with free- head boundary conditions). For piles with fixed head boundaries (i.e. rotation restrained piles) shear deformations could be of significant influence. To study this problem, a coupled shear flexure interaction model for axial-bending-shear behavior coded in OpenSees was applied to a 0.61 m (2 ft) diameter flagpole and a 0.61m (2 ft) diameter fixed head pile specimen to investigate the possible influence of shear deformations to the overall pile responses. The surrounding soil was represented by p-y curves derived from prior large scale testing on piles with similar boundary conditions. Analysis results show that for flagpole piles, shear forces and shear deformations were insignificant. Considerable contributions of pile shear displacements and forces were observed for the fixed head pile, with shear displacements contributing up to 40% of the total pile displacement. Results suggest that nonlinear shear deformations for reinforced concrete piles should be considered for fixed-head or similar conditions, and that currently used p-y curves may underestimate the actual lateral pile displacement and possibly lead to unsafe design for the particular boundary condition.

Jan 1, 2012

By Thomas M. Gurtowski

The New Pacific Northwest Baseball Park, now known as Safeco Field, is located directly south of the Kingdome in Seattle, Washington, and will be the new home of the Seattle Mariners baseball team. The location of the ball field is shown on Figure 1, Vicinity Map. The seating capacity is 45,600, and outfield distances are 331 feet in left, 405 feet in center, and 326 feet in right field. The overall dimensions of the stadium are 680 by 800 feet. It is bordered on the east by the Burlington Northern Santa Fe Railroad main line. A unique aspect of this ballpark is the retractable roof with a north-south span length of 660 feet. The roof consists of three separate sections that roll on elevated rails running east-west on the north and south sides of the stadium. The soil conditions consisted of near-surface fill underlain with alluvial and Estuarine deposits to depths of 60 to 80 feet. The bearing soils consisted of very dense, glacially overridden deposits. Groundwater is 4 to 7 feet below the ground surface, and the alluvial deposits are subject to liquefaction during a strong motion earthquake.

Jan 1, 1998

By Ray Schmahl

The Glenwood Canyon is a 13 mile long river gorge formed by the Colorado River approximately 2 miles East of Glenwood Springs, Colorado and approximately 150 miles West of Denver Colorado, (See Drawing #1). The canyon walls rise some 800 feet from the river elevation on either side of the river. The South-side river bank is occupied by the Denver and Rio Grande Western Railroad. The Northside is currently occupied by completed sections of Interstate 70 and US Highway 6. The railroad was built in the late 1800&apos;s and a hydroelectric power generating station was built in about the center of the canyon in the early 1900&apos;s. The Highway 6 platform was completed in the 1930&apos;s. The design and alignment for Interstate 70 thru Glenwood Canyon began in the early 1970&apos;s. The Highway thru Glenwood Canyon was designated a scenic Highway by the United States Congress, thereby allowing certain deviations from standard Interstate requirements. Environmentalists objections to the construction of Interstate Highways thru Glenwood Canyon resulted in especially careful design to avoid adverse environmental impacts. As a result, in many areas the new Highways will have restored the canyon to its more native configuration than what was the case in the building of the US 6 Highway platform.

Jan 1, 1990

By Bengt H. Fellenius

THIS PAPER deals with the analysis of results from axial testing of vertical single piles, i.e. the most common field test per-formed. Despite the numerous tests which have been carried out and the many Papers which have reported on such tests and the analysis thereof, the understanding of pile test loading in current engineering practice leaves much to be de-sired. The reason for this is that the engineers have concerned themselves with mainly only one question: "Does the pile have a certain least capacity?", finding little of practical value in analysing the actual capacity and the pile-soil interaction. This Paper aims to show that engineering value can be gained from elaborating on a pile test ? during the actual testing in the Held, as well as in the analysis of the results. The first portion of the notes make use of an earlier Paper by the author (Fellenius. 1975). However, additional views and recent literature have been incorporated.

Jan 1, 1988

By Karsten Beckhaus

"Abstract Tremie concrete for special geotechnical works needs special properties, especially during the casting process. Today’s execution standards for bored piles and diaphragm walls, EN 1536 and EN 1538, as well as the draft version of concrete standard EN 206, all comprise regulations for deep foundation concrete which have not been changed for decades. Considering the recent development in concrete technology at the same time and its actual state-of-the-art, it is essential to develop new normative specifications and specification requirements.GeneralTo allow the required integrity and quality after placing and hardening, concrete for structural elements like bored piles or diaphragm walls, used as foundations of high-rise buildings or as retaining structures for large and deep building pits, must have adequate workability and stability.In addition to requirements on mechanical properties and on durability, both of which have increased within the last decades, concrete must be suitable for being cast in deep or extremely deep excavations, see figure 1. Today’s specialist foundation engineering machinery makes it possible to drill or cut down to in excess of100 m depth. Concrete technology has developed and allows the use of high performance concrete for deep foundations. But is this capability represented by actual regulations?It has become very common for the industry to supply or use concrete with low water cement ratios, nevertheless highly flowable and set-retarded for several hours if needed. Very low water cement ratios allow design strength of 60 MPa or higher (Larisch, 2011), and a very low porosity which is required for a long service life in aggressive conditions, e.g. by chlorides.To achieve best performance, it is obvious that the concrete must completely fill the excavation and fully embed the reinforcement. As vibration of deep foundation concrete is (usually) not allowed and was anyway inefficient, deep foundation concrete must be designed to self-compact under hydrostatic pressure. Generally, it must be considered that after placement the concrete’s quality cannot be influenced anymore. Therefore, both the pouring procedure and the concrete quality must be adequate."

Jan 1, 2014