Harry G. Poulos

Harry G. Poulos
The University of Sydney · School of Civil Engineering

DScEng

About

306
Publications
381,916
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
13,912
Citations
Citations since 2017
20 Research Items
5824 Citations
201720182019202020212022202302004006008001,000
201720182019202020212022202302004006008001,000
201720182019202020212022202302004006008001,000
201720182019202020212022202302004006008001,000
Additional affiliations
November 2001 - present
The University of Sydney
Position
  • Professor Emeritus
Education
March 1957 - November 1960
The University of Sydney
Field of study
  • Civil Engineering

Publications

Publications (306)
Article
Full-text available
Historically, deep foundations in weak rock have been designed as friction elements using frictional resistance (fs), calculated from the unconfined compressive strength (UCS) of rock. Most of the published correlations of fs to UCS were developed based on load tests on low-capacity piles in specific geological conditions, using UCS values not nece...
Preprint
Full-text available
Historically, deep foundations in weak rock have been designed as friction elements using frictional resistance (f s ) calculated from the unconfined compressive strength (UCS) of rock. Most of the published correlations of f s to UCS were developed based on load tests on low-capacity piles in specific geological conditions, using UCS values not ne...
Chapter
Geotechnical failure may be the result of natural events but is often due to engineering construction in (or using) geological materials such as soil or rock. Failure may occur during construction or at some time after construction is complete, and may take place if some aspect of the engineering design is inadequate, erroneous or overlooked. Becau...
Preprint
Full-text available
This paper describes an approach for utilizing in-situ measurements of shear wave velocity Vs to carry out preliminary and check design calculations for shallow and deep foundations. For estimates of foundation movements, Vs can be used directly to estimate the small-strain stiffness of the soil or rock strata, while for ultimate capacity calculati...
Article
Full-text available
Τhis paper presents an analytical method for calculating the steady-state impedance factors of pile groups of arbitrary configuration subjected to harmonic vertical loads. The derived solution allows considering the effect of the actual pile geometry on the contribution of pile-soil-pile interaction to the response of the group, via the introductio...
Article
Full-text available
This article evaluates two distinct external effects on the settlement results from standard analyses of piled raft foundation systems. The influence of the excavation level and the influence of the number of piles underneath the pile will be separately assessed by two independent analyses for two published case histories, respectively a house loca...
Article
Full-text available
Barrettes having rectangular cross-sections can be analysed using finite elements, but this requires a three-dimensional non-linear computation which can be time consuming. Therefore, in this paper, the use of simple means of analysis based on conventional piles of circular cross-section is examined. Equivalent dimensions are chosen for the circula...
Article
Full-text available
Dynamic analyses of piles subjected to both vertical and horizontal loading under seismic conditions are of great significance to geotechnical and practicing engineers and the numerical methodology proposed in the present study fills the existing research gap. A finite difference based computer program FLAC3D is used to model a single pile and obta...
Article
Piles and prefabricated vertical drains (PVDs) are two well-established inclusions used by geotechnical practitioners when dealing with soft compressible foundations. Induced movements in highly compressible soil can adversely influence the pile response by inducing additional movements and stresses in the piles. Especially, undesirable soil–pile i...
Article
Full-text available
This paper presents a collection of some of the available published information on geological and geotechnical characteristics of some Middle Eastern countries within the Arabian Peninsula. For each of the countries considered, a brief summary is given of the geological history, typical geotechnical profiles and typical geotechnical parameters, and...
Conference Paper
This paper sets out an approach for utilising the small strain shear modulus of a soil to derive deformation parameters for foundation settlement prediction. This approach is an extension of that described by Mayne and his co-workers, with consideration being given also to the drained behaviour as well as the undrained behaviour of the soils. Both...
Article
Full-text available
This article analyses the effect of the excavation level on the settlement results from a standard analysis of a piled raft system. For that, a published case history that involved a house located in Gothenburg, Sweden by Hansbo (1993) was examined. This structure was founded over a soft, highly plastic marine clay of varying thickness, where the f...
Article
Full-text available
This paper presents a simple approximate pseudostatic method for estimating the maximum internal forces and horizontal displacements of a pile group located in a soil slope. The method is extension of an existing similar method developed by the authors for the case of a horizontal ground surface. The method employed for horizontal ground case invol...
Article
The concept of modulus of subgrade reaction has been employed within the engineering world for almost 150 years. It has been especially embraced by structural engineers who have found it convenient to represent the behaviour of the ground supporting their structures by elastic springs. Despite the best efforts of the geotechnical profession to diss...
Article
Full-text available
Deep excavations inevitably induce stress relief and soil movement, which may affect the safety and serviceability of nearby existing pile foundations. Although the effects of excavation on adjacent piles have been studied, excavation-induced pile settlement and change of shaft resistance deserve more investigation. In this paper, centrifuge simula...
Article
Full-text available
This paper will review some of the challenges faced by designers of foundations for very tall buildings, primarily from a geotechnical viewpoint. Some characteristic features of such buildings will be reviewed and then the options for foundation systems will be discussed. A three-stage process of foundation design and verification will be described...
Article
Full-text available
The design of tall building foundations involves a systematic process which incorporates ground investigation, ground characterization, preliminary design of the foundation system for the anticipated structural loads, detailed foundation design, load testing of the proposed foundations, modification of the foundation design, if appropriate, and mon...
Article
Full-text available
ABSTRACT: The design of tall building foundations involves a systematic process which incorporates ground investigation, ground characterization, preliminary design of the foundation system for the anticipated structural loads, detailed foundation design, load testing of the proposed foundations, modification of the foundation design, if appropriat...
Article
This paper describes kinematic seismic interaction analysis of square pile groups in homogeneous soil deposits, focusing on bending moments induced by the transient motion. Analyses were performed by means of a three-dimensional (3D) numerical procedure able to account for both pile–soil–pile interaction and radiation damping. The seismic motion wa...
Article
Full-text available
Low-strain testing of piles is routinely performed by striking the pile head with a small hand-held hammer, usually aiming for the pile centre, and measuring the vertical velocity response by means of a receiver placed also on the pile head. In practice, however, it is impossible for the operator to perfectly align the point of impact with the pile...
Article
Full-text available
The interpretation of low strain integrity tests of piles is commonly based on methods developed around the one-dimensional wave propagation theory. In reality, waves resulting from the impact of the hammer on the pile head propagate in three dimensions, and the validity of the plane-front assumption is rather questionable for the cases where the s...
Article
Full-text available
This paper describes the foundation design process that has been adopted for some of the world’s tallest buildings, including the Burj Khalifa in Dubai and the Incheon 151 Tower in Korea. The foundation system for these super tall towers is a piled raft, founded on deep deposits of soils and rocks. The foundation systems are required to support the...
Chapter
The paper sets out a framework for investigating the possible causes of foundation failures in a systematic manner. Aspects relating to foundation failure such as conditions for failure, factors affecting geotechnical foundation resistance, structural foundation resistance, factors affecting applied loads and structural actions, development and tes...
Article
Full-text available
An important aspect of the design of pile groups and piled rafts is the checking of axial loads, lateral loads and bending moments in each of the piles to ensure that they are structurally sound, but most commercially available pile analysis programs assume that the raft or pile cap is rigid. This paper explores the importance of taking the flexibi...
Conference Paper
Full-text available
An important aspect of the design of pile groups and piled rafts is the checking of axial loads, lateral loads and bending moments in each of the piles to ensure that they are structurally sound, but most commercially available pile analysis programs assume that the raft or pile cap is rigid. This paper explores the importance of taking the flexibi...
Article
Full-text available
This paper reviews some of the challenges that face designers of foundations for very tall buildings, primarily from a geotechnical viewpoint. Some characteristic features of such buildings will be reviewed and then the options for foundation systems will be discussed. A three-stage process of foundation design and verification will be described, a...
Article
This paper describes a case history of a deep cement mixed (DCM) column-supported embankment that is part of the Ballina Bypass section of the Pacific Highway Upgrade project in Australia. Measured settlements during and after construction of the embankment were significantly greater than the predicted settlements and suggested that the DCM columns...
Conference Paper
Full-text available
: Four computer programs CLAP, PIGLET, REPUTE and PLAXIS 3D, have been used for the analysis of pile groups subjected to applied loadings. The programs are briefly introduced and the basis of each program is described. The limitations of each program are discussed, together with the way in which the soil, piles and pile caps are modeled. The progra...
Article
Full-text available
During the past decade, the application of vacuum preloading for stabilising soft coastal clay and other low-lying estuarine soils has become popular in Australia. The cost-effectiveness is a major factor in most projects in view of the significantly reduced time for achieving a relatively high degree of consolidation. Due to an increase in trade a...
Article
Geotextile-reinforced embankments over deep cement mixed (DCM) columns are widely used for the construction of highway embankments over soft clay with low shear strength and high compressibility. Numerical modeling based on the FEM is widely used to investigate the behavior of these embankments during construction and serviceability, incorporating...
Conference Paper
Full-text available
As part of the foundation design verification process for a super-tall tower in South Korea, a program of pile load testing was initiated. The test program involved vertical load tests on four piles and a lateral load test on two piles, jacked against each other. The vertical load tests used the Osterberg cell method, with two sets of Osterberg cel...
Article
Deep cement mixed (DCM) columns with geosynthetic reinforcements are used as integrated foundation systems for construction of embankments over soft soils. Several design guidelines are available in the literature for these embankments based on the soil arching and membrane theories. This paper identifies some inconsistencies in applying these desi...
Article
Full-text available
Negative skin friction (NSF) can induce an increased compressive force on piles, called dragload, and additional pile settlement caused by the downward pull of the soil, called downdrag. To investigate the efficiency of shielding effects on dragload and downdrag of piles, centrifuge tests have been carried out to study the shielding mechanisms crea...
Book
Full-text available
Due to the high development of the pile foundations technology and its wide application to the civil and maritime engineering, the response of a pile foundation system became a topic of major interest to the consultant engineers, contractors, control offices and research establishments. This book compiles the contribution of 12 authors well known b...
Conference Paper
Full-text available
Ground investigations for a high-rise tower in Jeddah Saudi Arabia revealed the presence of cavities in some of the boreholes. It was decided that a piled raft would be a suitable foundation option as it would provide a measure of redundancy in case some of the piles encountered cavities. Under such circumstances, the raft would permit the transfer...
Article
Full-text available
This paper deals with the re-assessment of foundation settlements for the Burj Khalifa Tower in Dubai. The foundation system for the tower is a piled raft, founded on deep deposits of calcareous rocks. Two computer programs, Geotechnical Analysis of Raft with Piles (GARP) and Non-linear Analysis of Piled Rafts (NAPRA) have been used for the settlem...
Conference Paper
Full-text available
Four computer programs CLAP, PIGLET, REPUTE and PLAXIS 3D, have been used for the analysis of pile groups subjected to applied loadings. The programs are briefly introduced and the basis of each program is described. The limitations of each program are discussed, together with the way in which the soil, piles and pile caps are modeled. The programs...
Article
Design procedures for Geosynthetic Reinforced Column Supported (GRCS) embankments generally consider the sliding failure for external stability and the shear failure mode for internal stability. However, other failure modes such as collapse failure, slip circle failure, punching shear failure around column heads (overall or local), and bending fail...
Chapter
Deep cement mixed columns are widely used to support highway embankments constructed on soft compressible ground. In current design practice, it is assumed that the performance of Geosynthetic Reinforced Column Supported (GRCS) embankments is similar to that of pile supported embankments and the consti-tutive behavior of DCM columns is simulated as...
Conference Paper
Full-text available
Two computer programs, GARP and NAPRA, used for the analysis of piled raft foundations are briefly introduced and the basis of each program is described. The programs are compared first for the analysis of a simple problem involving a rectangular raft with a relatively small number of piles, and reasonable agreement is found between the computed be...
Conference Paper
Full-text available
This paper sets out the principles of a limit state design approach to design a pile or piled raft foundation system for tall buildings, and involves three sets of analyses: 1. An overall stability analysis in which the resistances of the foundation components are reduced by the appropriate geotechnical reduction factor and the ultimate limit state...
Conference Paper
This paper evaluates a simple approximate pseudostatic method for estimating the maximum internal forces and horizontal displacements of a pile group located in a soil slope. The method is an extension of an existing similar method developed by the authors for the case of a horizontal ground surface. The method for horizontal ground involves two ma...
Conference Paper
Full-text available
This paper describes a process by which pile load test data can be used to assist in the prediction of pile foundation settlements. In the interpretation of the load test results, the critical importance of making allowance for the load test setup and possible interaction effects is emphasized, because of the potential for over-estimation of pile s...
Article
Full-text available
Piled raft foundations are increasingly being recognised as an economical and effective foundation system for tall buildings. This paper sets out some principles of design for such foundations, including design for the geotechnical ultimate limit state, the structural ultimate limit state and the serviceability limit state. The advantages of using...
Article
Full-text available
A 151 storey super high-rise building located in an area of reclaimed land constructed over soft marine clay in Songdo, Korea is currently under design. This paper describes the design process in developing the foundation system of the super-tall tower, which is required to support the large building vertical and lateral loads and to restrain the h...
Article
Full-text available
Comparisons are made between the measured and computed axial and lateral responses of piles supporting a viaduct bridge in Singapore. The computed values were obtained from programs that use simplified boundary-element analyses for axial and lateral pile response, combined with input free-field ground movements obtained from approximate closed-form...
Article
Full-text available
This paper employs a modified nonlinear boundary element approach to analyze the response of offshore piles subjected to external soil movements arising from submarine slides. Theoretical solutions for a realistic hypothetical offshore pile computed by the approach are presented and discussed. The analysis is then used to analyze the behaviour of t...
Article
Full-text available
This paper describes a simple nonlinear pile-soil interface model incorporated into a modified boundary element analysis to simulate the behaviour of piles in calcareous soils subjected to both static and cyclic loading. A shaft resistance degradation model and a cyclic secant soil modulus degradation model are proposed, and implemented in the nonl...
Article
When a pile is driven into clay, horizontal and vertical movements are developed in the soil surrounding the pile. These movements will tend to develop axial forces and bending moments in adjacent piles that have already been installed. Possible consequences for these piles are (i) structural damage or cracking (of concrete piles) arising from the...
Article
Full-text available
This paper describes an approach for the design of piles to reinforce slopes, involving three main steps: (1) evaluating the shear force needed to increase the safety factor to the desired value; (2) evaluating the maximum shear force that each pile can provide to resist sliding of the potentially unstable portion of the slope; and (3) selection of...
Article
Full-text available
In this paper, a two-stage analysis involving the finite element method and the boundary element method is used to study pile response due to excavtion-induced lateral soil movements, focusing on unsupported excavations in clay layers. It is shown that the pile response in this case is different from that caused by excavations which are braced. Des...
Article
Full-text available
This paper reviews the contributions of the late Victor de Mello to foundation engineering and attempts to highlight the insights that he provided in a number of key areas, including foundation design principles, the bearing capacity of shallow foundations, the axial load capacity of deep foundations, and the behaviour of foundations incorporating...
Conference Paper
Full-text available
Pile groups subjected to lateral loadings have in the past been treated as a group of piles that resist lateral loading due to the lateral pressure acting on the pile shaft. The effect of the cap or raft in resisting the lateral loading has often been neglected although cohesive or friction forces may be acting across the base of the cap. In this p...
Article
This paper evaluates a simple approximate pseudostatic method for estimating the maximum internal forces and horizontal displacements of pile group subjected to lateral seismic excitation. The method involves two main steps: (1) computation of the free-field soil movements caused by the earthquake, and (2) the analysis of the response of the pile g...
Article
In this paper, a numerical procedure based on the finite element method is outlined to investigate pile behaviour in sloping ground, which involves two main steps. First a free-field ground response analysis is carried out using an effective stress based stress path model to obtain the ground displacements, and the degraded soil stiffness and stren...
Article
Full-text available
This paper presents a method of analysis of the behaviour of piled rafts in clayey soils, in which a deep excavation was necessary for buildings with two or more basements. In these cases, the piled raft foundations are called a ''com-pensated piled raft.'' The soil stresses reduce due to excavation, and the reloading of the soil should be taken in...
Conference Paper
This paper sets out the principles of using computer programs for pile group response to design a pile foundation system via a limit state design approach. The approach involves three sets of analyses: (1) An overall stability analysis; (2) A serviceability analysis; (3) An analysis to obtain the structural actions for structural design of the raft...
Article
Full-text available
High-rise buildings are usually founded on some form of piled foundation subject to a combination of vertical, lateral and overturning forces. However, conventional methods for assessing stability may not be adequate when designing such foundations because they tend to focus on resistance under vertical loading. This paper sets out an ultimate-limi...
Article
Soil liquefaction during strong ground shaking results in almost complete loss of strength and stiffness in the liquefied soils, and consequent large lateral ground displacements. Both cyclic displacements during the intense ground shaking and development of liquefaction, and especially post-liquefaction lateral displacement due to spreading of liq...
Article
Forensic geotechnical engineering is gaining increasing importance in many countries where foundation failures may lead to litigation and even criminal action. This paper sets out a framework for forensic geotechnical assessments of foundation failures, involving a systematic consideration of the various factors that may have influenced the failure...
Article
This paper presents a method of analysis of pile groups subjected to vertical and moment loading. It allows consideration of non-ideal situations in which not all piles in the group are the same, some piles may contain defects, and the group configuration may change during construction and operation. The paper sets out a simplified analysis which a...
Article
Pile foundations located within consolidating ground are commonly subjected to negative skin friction (NSF) and failures of pile foundations related to dragload (compressive force) and downdrag (pile settlement) have been reported in the literature. This paper reports the results of four centrifuge model tests, which were undertaken to achieve two...
Article
Full-text available
Misconceptions remain in the minds of some pile designers when negative friction effects have to be taken into account. This paper outlines some of these misconceptions, and then describes a relatively straightforward approach for designing piles subjected to negative friction. This approach relies on the consideration of the portion of the pile th...
Article
Geotechnical engineers dealing with embankment construction over soft ground encounter major challenges due to low bearing capacity and excessive settlement characteristics of soft soils. As a result, a wide range of technologies has been developed to support embankment foundations on soft ground. One such technology is the use of geosynthetic rein...
Article
Full-text available
Ground movements can arise from a large number of sources and can have a significant effect on nearby piles and deep foundations. The loading of the piles by ground movements is a different mechanism to that arising from direct applied loading to the pile head, and consequently it is not generally possible to adequately analyze the effects of groun...
Conference Paper
Full-text available
In this paper, the principles of a piled raft analysis, employing a combination of finite element and boundary element analyses, are described. This analysis is implemented via a computer program GARP (Geotechnical Analysis of Rafts with Piles). In this program, the raft is analysed via a finite element formulation for a plate, the piles are consid...
Conference Paper
Full-text available
...
Conference Paper
Full-text available
A method of analysis is presented for piled raft foundations where the piles exhibit non linear load-deflection behaviour. The raft is analysed through the use of finite element methods, while the piles are treated as springs having a variable stiffness, so as to model any non-linear behaviour. The soil is treated as an elastic medium that may cons...