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This document is a closure to a previous paper titled "Foundation Settlement and Tilt of Millennium Tower in San Francisco, California." The authors respond to comments and questions raised by discussers regarding the design, construction, and analysis of the tower's foundation movements. They emphasize that their goal was to objectively document the data and provide interpretations of the soil deformation mechanisms that caused the settlements. They encourage further investigation and analysis of the case history to advance foundation engineering practices in dense urban environments. [Extracted from the article]

The San Jacinto Monument was built in 1936 to celebrate the 100 year anniversary of the battlefield victory that gave Texas its freedom. Ray Dawson was in charge of the foundation design and decided to instrument the foundation to monitor the settlement of the Monument. The settlement has been recorded since 1936 and provides a very valuable long-term record. This settlement and other geotechnical data were studied and reported by Briaud and his co-authors in 2007. That study was based on data available at the time, which was primarily from a 61-m-deep boring in 1953. In 2007, Fugro and Texas A&M University drilled a new boring with sampling to a depth of 78 m, conducted in situ tests to 36 m, and laboratory tests on the samples recovered. Updated settlement calculations are provided using this new data; they show reasonably good agreement with modern settlement techniques. One of the issues possibly affecting the settlement readings is the subsidence of the ground surface, which can reach 3 m in that area of Houston. A second part of this article presents calculations and numerical simulations to evaluate the influence of subsidence on the recorded settlement of the Monument. It is shown that the true settlement of the SJM is 295 mm while the measured settlement is 328 mm. The reduction is due to the different influence of the subsidence on the settlement of the shallow benchmark and of the Monument. [ABSTRACT FROM AUTHOR]

The discussers considered two possibilities: (1) 10% of the pile load transferred to the pile toe and 90% to the pile shaft and (2) 50% of the pile load transferred to the pile toe and 50% to the pile shaft. With the loading carried by the raft and the pile group, the settlement of the piled raft could be simply evaluated by the Aoki and Lopes ([1]) equations. The calculation of the raft and pile group stiffness allowed the estimation of the load shared by the raft and that shared by the pile group. [Extracted from the article]

This paper reports advances in the prediction of spudcan resistance profiles during installation and preloading, based on the soil flow mechanisms observed in model tests and numerical analysis, and taking into account strain softening and rate dependency on the soil strength. Deep penetration of spudcan foundations was simulated for 14 case histories reported from different locations in the Gulf of Mexico, where the soils were single layer, predominantly normally to lightly overconsolidated clay. Axisymmetric and three-dimensional analyses were carried out using two large deformation finite-element (LDFE) approaches, modifying the simple elastic-perfectly plastic Tresca soil model to allow strain softening and strain-rate dependency of the shear strength. The field data were compared with the results of the finite-element analyses and with predictions using various design approaches. Excellent agreement was found, particularly when a mechanism-based design approach was used that differentiated between conditions before and after backflow of soil above the penetrating spudcan. [ABSTRACT FROM AUTHOR]

A new concept with respect to offshore wind turbines, the bucket foundation, is known in the oil and gas industry, although the load conditions for wind turbines are significantly different. An extensive number of loading tests with small-scale bucket foundations subjected to combined loading were carried out in the geotechnical laboratory at Aalborg University in Aalborg, Denmark. Tests were performed on buckets of various sizes, embedment ratios, and load paths on saturated dense Aalborg University Sand No. 1. The experimental results were used to evaluate the behavior of the bucket foundations in accordance with the macromodel approach. An expression to describe the combined capacity of bucket foundations was developed by calibrating the failure criteria for bucket foundations. [ABSTRACT FROM AUTHOR]

Repetitive loading can induce volumetric and shear strain accumulation in soils and affect the long-term performance of engineered and natural geosystems. A hybrid numerical scheme based on the FEM is implemented to analyze problems where a very large number of cycles is involved. The numerical approach combines a classical mechanical constitutive model to simulate the static load and the first load cycle and empirical accumulation functions to track the accumulation of deformations during repetitive loading. The hybrid model captures fundamental characteristics of soil behavior under repetitive loading, such as threshold strains, terminal density, and ratcheting response; it also predicts volumetric and shear strains as a function of the static stress obliquity, the number of load cycles, and the plastic strain during the first load cycle. The proposed numerical scheme is used to analyze shallow foundations subjected to repetitive loads. Results show the evolution of vertical settlement, horizontal displacement, footing rotation, and stress redistribution within the soil mass as the number of load cycles increases. Displacements and rotation are more pronounced as the static factor of safety decreases and the cyclic load amplitude increases. [ABSTRACT FROM AUTHOR]

This study presents a centrifuge modeling approach to characterize the transient thermomechanical response of energy foundations during heating-cooling cycles to provide data for calibration and validation of soil-structure interaction models. This study focuses on the response of a scale-model energy foundation installed in an unsaturated silt layer with end-bearing boundary conditions. The foundation response was assessed using embedded strain gauges and thermocouples. Other variables monitored include foundation head displacements, soil surface displacements, and changes in temperature and volumetric water content in the unsaturated silt at different depths and radial locations. Measurements during the initial heating process indicate that the thermal axial stress is greater near the toe of the foundation as a result of the restraint associated with mobilization of side shear resistance along the length of the foundation. The thermal axial strains were close to the free-expansion thermal strain near the soil surface and decreased with depth. The thermal axial displacements calculated by integrating the thermal axial strains correspond well with the independently measured head displacements. The mobilized side stresses calculated from the thermal axial stresses increased with height and were consistent with the shear strength of unsaturated silt. During successive heating-cooling cycles, slight decreases in upward thermal head displacement were observed because of changes in the stiffness of the unsaturated soil from thermally induced water flow away from the foundation and potential downdrag effects. However, little change in the thermal axial stress was observed during the heating-cooling cycles. [ABSTRACT FROM AUTHOR]

The design of a railway track substructure requires a realistic understanding of the resilient behavior of the underlying track foundation materials, namely, the subballast and subgrade layers. Currently, the best available method of characterizing the resilient behavior of track foundation materials is through the execution of cyclic triaxial tests, although these do not have the ability to impose principal stress rotation (PSR) on test specimens. A previous paper by the authors demonstrated that PSR increases the rate of permanent strain development. This paper reports on the effects of PSR on the resilient behavior of track foundation materials. Four different reconstituted soils selected to represent typical track foundation materials were subjected to undrained cyclic and torsional shear tests in a hollow-cylinder apparatus. It was established that PSR reduces the resilient modulus of the materials compared with cyclic loading without PSR. The effects of PSR as a function of clay content, overconsolidation ratio (OCR), and consolidation regime (isotropic or anisotropic) were also investigated. [ABSTRACT FROM AUTHOR]

Bridge scour is the loss of soil by erosion because of water flowing around bridge supports. Scour has been the number one cause of bridge failure in the United States with an average annual rate of 22 bridges collapsing or being closed owing to severe deformation. This paper addresses three topics related to bridge scour. First, a set of databases was used to quantify the statistical parameters associated with the scatter between the predicted and measured pier scour depth, as well as the probability that a deterministically predicted pier scour depth will be exceeded. These databases also were used to provide the bias factors in current predictions. Secondly, these statistical parameters were used to develop a reliability-based load and resistance factor design for shallow and deep foundations subjected to scour. The goal was to provide a design procedure where the reliability of the foundation is the same with or without scour. Reliability only addresses the probability of success and, therefore, of failure. Finally, the discussion was broadened by using the concept of risk defined as the probability of failure times the value of the consequences. In this third part, the risk associated with bridge scour was quantified and compared to risks associated with other engineering structures. Target values of acceptable risk were recommended as part of the conclusions. [ABSTRACT FROM AUTHOR]

The article discusses the article "The State of the Practice in Foundation Engineering on Expansive and Collapsible Soils" by William N. Houston and John D. Nelson. The authors of the article say that a careful designer should perform sufficient analyses or investigation to set up within reasonable certainty the design active zone for the life of the structure.

During the past few decades, soil nailing has been widely used for stabilizing slopes and excavations. The nail-soil interface shear resistance in the passive zone of a slope or excavation is a critical parameter in design. In this paper, an analytical study is proposed to investigate the progressive pullout response of a soil nail. Pullout process is divided into three typical phases: (1) the initial pure elastic phase during which the nail-soil interface follows a linear elastic stress-displacement relationship; (2) the elastic-plastic phase during which a transition point presents dividing the elastic and plastic zones; and (3) the final pure plastic phase. A comparison study between calculations and laboratory test data are presented to examine the effectiveness of the method. In addition, a comprehensive parametric study is performed to assess the effects of several key factors on the pullout resistance of a soil nail. These factors include the length and diameter, length of plastic zone, and the elastic modulus of a soil nail. Main research findings are presented and discussed to gain a better understanding of the progressive interaction between soil and soil nail. [ABSTRACT FROM AUTHOR]

A capillary barrier as a cover system is a two-layer system of distinct hydraulic properties to prevent water infiltration into the underlying soil by utilizing unsaturated soil mechanics principles. This paper illustrates the application of the capillary barrier system on a slope that experienced shallow slip failures to prevent future rainfall-induced slope failures. In this study, the capillary barrier system was designed as a cover system for residual soil slopes with a steep slope angle under heavy rainfall conditions of the tropics. The capillary barrier system was constructed using fine sand as the fine-grained layer and granite chips as the coarse-grained layer. Both layers were contained in a cellular confinement system. The slope was instrumented with tensiometers and piezometers. The tensiometers were installed at different depths from about 0.5 m to 2.0 m below the slope surface. An adjacent original slope without the capillary barrier system was also instrumented using tensiometers to investigate the performance and effectiveness of the capillary barrier system in reducing rainwater infiltration and maintaining negative pore-water pressure in the slope. The detailed installation of a matric suction measurement device is discussed comprehensively in this paper. The measurement results showed that the capillary barrier system was effective in maintaining the negative pore-water pressures during rainfalls, particularly on the crest of the slope. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the behavior of an eccentrically loaded model ring footing resting on a compacted replaced layer of sand that overlies an extended layer of loose sand. Particular emphasis is placed on the potential benefits of reinforcing the replaced sand layer with geogrid reinforcement. Load configuration was designed to simulate ring footings under vertical loads and overturning moment caused by lateral loads. Several configurations of geogrid layers, number, and stiffness were used to study ring footings with different inner-to-outer-diameter ratios and load eccentricities. The effect of the depth and the relative density of the replaced sand layer was also investigated. Test results indicate that the behavior of an eccentrically loaded ring footing significantly improves with an increase in the depth and the relative density of the replaced compacted sand layer. However, the inclusion of soil reinforcement not only leads to a significant reduction in the depth of the replaced sand layer but also causes a considerable increase in the bearing capacities of the eccentrically loaded rings, leading to the cost-effective design of the footings. On the basis of the test results, the effects of different parameters are presented and discussed. [ABSTRACT FROM AUTHOR]

The nonlinear response of shallow foundations has been studied experimentally and analytically. However, the engineering community is not yet convinced of the applicability of such concepts in practice. A key prerequisite is the ability to realistically model such effects. Although several sophisticated constitutive models are readily available in the literature, their use in practice is limited, because (1) they typically require extensive soil testing for calibration; (2) as they are implemented in highly specialized numerical codes, they are usually restricted to simple superstructures; and (3) in most cases, they can only be applied by numerical analysis specialists. Attempting to overcome some of these difficulties, this paper develops a simplified but fairly comprehensive constitutive model for analysis of the cyclic response of shallow foundations. On the basis of a kinematic hardening constitutive model with Von Mises failure criterion (readily available in commercial finite element codes), the model is made pressure sensitive and capable of reproducing both the low-strain stiffness and the ultimate resistance of clays and sands. Encoded in ABAQUS through a simple user subroutine, the model is validated against (a) centrifuge tests of shallow footings on clay under cyclic loading and (b) large-scale tests of a square footing on dense and loose sand under cyclic loading, conducted in the European Laboratory for Structural Analysis for the TRISEE project. The performance of the model is shown to be quite satisfactory, and discrepancies between theory and experiment are discussed and potential culprits are identified. Requiring calibration of only two parameters and being easily implemented in commercial FE codes, the model is believed to provide an easily applicable engineering solution. [ABSTRACT FROM AUTHOR]

The aim of this contribution is a practice-oriented prediction of environmental building vibrations. A Green’s functions method for layered soils is used to build the dynamic stiffness matrix of the soil area that is covered by the foundation. A simple building model is proposed by adding a building mass to the dynamic stiffness of the soil. The vertical soil-building transfer functions with building-soil resonances are calculated and compared with a number of measurements of technically induced vibrations of residential buildings. In a parametrical study, realistic foundation geometries are modeled and the influence of incompressible soil, deep stiff soil layering, soft top layers, and increasing soil stiffness with depth is analyzed. All these special soil models reduce the resonant frequency compared to a standard homogeneous soil. A physically motivated model of a naturally sedimented soil has a stiffness increasing with the square root of the depth and yields a foundation stiffness that decreases with foundation area considerably stronger than the relatively insensitive homogeneous soil. This soil model is suited for the Berlin measuring sites and reproduces satisfactorily the experimental results. [ABSTRACT FROM AUTHOR]

A study to evaluate corrosion rates was conducted using pile foundations abandoned during the reconstruction of I-15 through Salt Lake Valley, Utah. Corrosion rates were measured for 20 piles extracted from five sites after service lives of 34–38 years. Measurements were made of soil index properties, resistivity, pH, cation/anion concentrations, and water table elevation. The critical zone for corrosion was typically located within the groundwater fluctuation zone; but correlations with soil properties were generally poor. Despite low resistivity, average corrosion rates for pile caps in native soil were typically between 2 and 9 μm/year with a maximum of 19 μm/year and did not pose any structural integrity problems. Nevertheless, for abutment piles where chloride concentration was very high, the average pile corrosion rate increased to 13 μm/year within the embankment and the maximum corrosion rate was 48 μm/year in the underlying native soil. Based on data from this and previous studies, equations were developed to predict maximum corrosion loss for piles in nonaggressive soil as a function of time. [ABSTRACT FROM AUTHOR]

The I-15 Reconstruction Project in Salt Lake City, Utah required rapid embankment construction in an urban environment atop soft lacustrine soils. These soils are compressible, have low shear strength, and require significant time to complete primary consolidation settlement. Because of this, innovative embankment systems and foundation treatments were employed to complete construction within the approved budget and demanding schedule constraints. This paper evaluates and compares the construction time, cost, and performance of three embankment/foundation systems used on this project: (1) one-stage mechanically stabilized earth (MSE) wall supported by lime cement columns; (2) expanded polystyrene (geofoam) embankment with tilt-up panel fascia walls; and (3) two-stage MSE wall with prefabricated vertical drain installation and surcharging. Of the technologies evaluated, the geofoam embankment had the best performance based on settlement and rapid construction time considerations, but is more costly to construct than a two-stage MSE wall with PV drain foundation treatment. The one-stage MSE wall with lime cement treated soil was the most costly, and did not perform as well as expected; thus, it had only limited use on the project. [ABSTRACT FROM AUTHOR]

A study of the assumptions involved in the ultimate bearing capacity equation indicates the shortcomings of that equation and load test data confirm these shortcomings. A new approach using a normalized load settlement curve is proposed to alleviate these shortcomings and to obtain the complete load settlement curve for a footing in sand. The normalization consists of plotting the mean footing pressure divided by a measure of the soil strength within the depth of influence of the footing versus the settlement divided by the footing width. It is shown that the normalized load settlement curve for a footing is independent of footing size and embedment. It is proposed to obtain the normalized curve point-by-point from a soil test. Because the deformation of the soil observed under full-scale footings during loading indicates a barreling effect similar to the soil deformation around a pressuremeter probe, the preboring pressuremeter curve is used to obtain the footing curve. The new method consists of transforming the preboring pressuremeter curve point-by-point into the footing load settlement curve. Load tests and numerical simulations are used to propose a method for a rectangular footing near a slope subjected to an eccentric and inclined load. The new method gives the complete load settlement curve for the footing and alleviates the problems identified with the bearing capacity equation. [ABSTRACT FROM AUTHOR]

This note studies settlement ratio, Rs, of pile groups in sandy soils, defined as the ratio of the settlement of a pile group to that of a single pile at the same average load per pile. 31 cases of field pile-group load tests and the corresponding field single-pile load tests were collected for this study. More than one-half of the cases consist of 3-diameter spaced, 9-pile groups. Based on the field test data, statistical analyses of Rs at different load levels were conducted for pile groups with cap-ground contact (PGCs) and pile groups with freestanding caps (PGFs), respectively. The mean of Rs decreases with the load level for both PGCs and PGFs, whereas the coefficient of variation of Rs increases with the load level. The influence of cap-ground contact on Rs does not appear to be significant based on a comparison of the mean Rs values of these PGCs and PGFs. In addition, a comparative study on Rs and group resistance ratio Rr, which is defined as the ratio of the average resistance of a pile in a group to that of a single pile at the same settlement, was conducted to clarify possible misunderstanding between Rs and pile group efficiency factor η for driven pile groups in sandy soils. The value of Rs compares settlement at the working load and is often larger than unity. The value of η compares failure loads, which occur at different settlements for pile groups and their respective single piles. η is usually larger than unity due to soil densification and additional contributions from the cap-ground contact for PGCs. [ABSTRACT FROM AUTHOR]

Current design methods divide reinforced earth structures into walls and slopes by using an arbitrary face inclination of 70° as the boundary. The required maximum strength of reinforcement computed for reinforced walls are significantly higher than that computed for reinforced slopes even if the inclination is practically the same. Presented is a general analytical framework for design of flexible reinforced earth structures regardless of the slope face inclination. In fact, the framework is consistent for any structural geometry and any applicable slope stability analysis although, for demonstration purposes, the simple Culmann formulation is utilized for simple geometry with zero batter. Using an adequate slope stability formulation, the required tensile resistance of reinforcement for a given layout is calculated so as to produce the same prescribed factor of safety anywhere within the reinforced zone. That is, using the design shear strength of the soil, the required reinforcement resistance along each layer is computed to fully mobilize this shear strength for all possible slip surfaces. That is, a baseline solution is produced for an ideal long-term strength of reinforcement at any location. Consequently, the required strength of the connection between each reinforcement layer and the facing unit can also be determined. This connection strength, however, assumes small facing units with negligibly small shear and moment resistance. Parametric study is conducted to demonstrate the reasonableness of the presented framework. It is shown that the required tensile resistance and connection strength depend on factors such as: reinforcement length; intermediate reinforcement; percent coverage; and quality of fill. When compared with the current AASHTO design for walls, the required maximum long-term strength of the reinforcement as well as the required connection strength in the proposed approach are substantially smaller. [ABSTRACT FROM AUTHOR]

Traditional bearing capacity theories for the ultimate capacity of shallow foundations assume that the thickness of the bearing stratum is infinite. The presence of a hard layer within a certain depth below the foundation can significantly influence the unit load supported by the soil. Therefore the original bearing capacity equations should be modified to account for this condition in determining the ultimate bearing capacity. In order to evaluate this phenomenon further, model square and circular footing tests were performed on a bed of well-graded sand. Test beds were prepared at three different relative densities corresponding to loose, medium, and dense conditions: Dr=24, 57, and 87%, using five different sand layer thicknesses, H; H/B values of 0.5, 1, 2, 3, and 4, where B is the footing width. Results of the model scale footing tests show that the bearing capacity factor, Nγ, should be modified up to H/B=3, instead of H/B=1, as previously suggested. The footing shape factor, sγ, should account for both shape and finite layering. This technical note gives a description of the test methods and material used and presents the test results in comparison to previous results. [ABSTRACT FROM AUTHOR]

This paper identifies some of the causes of imperfections in real pile foundations and then examines their possible effects on pile behavior. The imperfections considered arise from two main sources, natural imperfections caused by the geological circumstances and imperfections related to the construction of the piles. In each case, single piles are considered first, and then pile groups are addressed separately. Case histories are presented to illustrate the effects on pile performance which are predicted by theoretical analyses. The analyses with which these examinations are carried out will still inevitably involve some degree of idealization, but at least attempt to incorporate the key “nonideal” aspects. The paper also discusses the particular problems involved in investigating and analyzing underperforming pile foundations and reviews some methods by which the consequences of imperfections may be overcome or ameliorated. [ABSTRACT FROM AUTHOR]

This paper presents the results of laboratory model tests on the influence of soil confinement on the behavior of a model footing resting on granular soil. Confining cylinders with different heights and diameters were used to confine the sand. The ultimate bearing load of a circular footing supported on a three-dimensional confined sand bed was studied. The studied parameters include the cell height, cell diameter, the depth to the top of the cell, and the embedded depth of footing. Initially, the response of a nonconfined case was determined and then compared with that of confined soil. The results were then analyzed to study the effect of each parameter. The results indicate that the bearing load capacity of circular footing can be appreciably increased by soil confinement. It was concluded that such reinforcement resists lateral displacement of soil underneath the footing leading to a significant improvement in the response of the footing. For small cell diameters, the cell–soil footing behaves as one unit (deep foundation), while this pattern of behavior was no longer observed with large cell diameters. The recommended cell heights, depths, and diameters that give the maximum bearing capacity improvement are presented and discussed. [ABSTRACT FROM AUTHOR]

The classic approach for static analysis and design for the effect of shear forces transmitted by shallow foundations is to modify the bearing capacity by introducing inclination factors to reduce the shear strength provided by cohesion, surcharge and self-weight in the standard bearing capacity equation. These static inclination factors are usually based on empirically derived relationships determined by laboratory and field tests. However, it is possible to derive them from limit analysis of a simple Coulomb-type mechanism and thereby extend the concept of inclination factors to the dynamic case giving values for seismic design. [ABSTRACT FROM AUTHOR]

Over the years, many methods have been developed to predict the settlement of shallow foundations on cohesionless soils. However, methods for making such predictions with the required degree of accuracy and consistency have not yet been developed. Accurate prediction of settlement is essential since settlement, rather than bearing capacity, generally controls foundation design. In this paper, artificial neural networks (ANNs) are used in an attempt to obtain more accurate settlement prediction. A large database of actual measured settlements is used to develop and verify the ANN model. The predicted settlements found by utilizing ANNs are compared with the values predicted by three of the most commonly used traditional methods. The results indicate that ANNs are a useful technique for predicting the settlement of shallow foundations on cohesionless soils, as they outperform the traditional methods. [ABSTRACT FROM AUTHOR]

Considers the probabilistic measures of foundation settlement on spatially random soil. Description of random field and finite element models of soil layer; Discussion of the single footing case; Analysis of the two footing case.

Presents information on a study which examined the ultimate bearing capacity of a strip footing located at the surface of a homogeneous soil. Solutions accounting for noassociativity of plastic flow; Analysis and discussion of results; Conclusions.

Deals with a study which presented an evaluation of predictions using input soil parameters from standard penetration test (SPT) and cone penetration tests correlations. Sand friction angle and subgrade modulus from SPT; Sensitivity to input parameters; Conclusion.

Examines the effects of reinforcement stiffness density, reinforcement/soil friction angle, facing/soil friction angle, backfill friction angle and facing rigidity on the behavior of continuous panel faced reinforced solid walls on a rigid foundation. Force distribution in the connections and reinforcement; Validity of conventional approaches.

The article offers the authors insights on the article "Interaction between Laterally Loaded Pile and Surrounding Soil," by Lusu Ni, Hai Lin, Anne Raich, and Muhannad T. Suleiman. Topics discussed include the use of tactile pressure sheets of measure stresses, soil pressure, and the measurement of horizontal soil stress distribution.

The article discusses the article "The State of the Practice in Foundation Engineering on Expansive and Collapsible Soils" by William N. Houston and John D. Nelson. The authors of the article say that the Standard of Care represents that standard that an engineer should be following in order to give the proper care to protect public health and safety.

The article presents response on the comment regarding the study on the minimum foundation mass for vibration control. It agrees with the discusser's findings that the dynamics of embedded foundations on layered soil cannot be studied through the simple design method proposed by the authors. It also recognizes the clearness of the author's method, which is based on the analog models of force vibration of a rigid disk.

The article the authors insights on the article "Interaction between Laterally Loaded Pile and Surrounding Soil," by Lusu Ni, Hai Lin, Anne Raich, and Muhannad T. Suleiman. Topics discussed include the use of the pressure distribution to simplify the analysis about pile rotation, the use of pressure sensors to measure soilpile interaction pressure, and the procedure of soil preparation.

The article discusses the study involving high-modulus columns for liquefaction mitigation. The authors resort to the Chinese criteria to support their argument of liquefaction and emphasize the similarity of ML/CL soils of the site to those encountered in Adapazari, Turkey which were presumed to have liquefied during the Kocaeli earthquake on the basis of observed displacements of building foundations. The authors compared performance of the supermarket building area which was strengthened through construction of jet-grout columns.

Comments on the article "Performance of Tension and Compression Anchors in Weathered Soil," by Nak-Kyung Kim in the December 2003 issue. Investigation on ground-anchor behavior; Need for researchers to be wary of defining "ultimate load" prior to full anchor failure being exhibited; Observation that the paper did not demonstrate anchor failure loads.

Responds to comments made by John T. christian and Gregory B. Baecher on the article 'Probabilistic Foundation Settlement on Spatially Random Soil.' Behavior of a single perfectly flexible footing modeled as a series of point loads applied directly to the surface of an elastic layer; Use of a first-order stochastic finite element model.

Discusses the paper `Large Model Spread Footing Load Tests on Geosynthetic Reinforced Soil Foundations,' by Michael T. Adams and James G. Collin.

The author discusses the paper "Shaft Resistance of Drilled Shafts in Clay" by Tanusree Chakraborty, Rodrigo Salgado, Prasenjit Basu and Mônica Prezzi. He commends the paper for examining the influence of the method of pile installation on the alpha factor used in determining the unit shaft resistance. He also describes the process of removal and reinsertion of the auger during the installation.

The authors focus on research into deep building foundations and its behavior under axial and lateral loading. They mention that the prediction of load-transfer curves, both for side resistance and for end bearing, allow for the analysis of deep foundations under a range of conditions. They talk about soil properties around deep foundations after installation and how the pile capacity under axial load differs depending on if the pile was driven into consolidated clay or loose cohesionless soil. They state that research can lead to an improvement of design methods of deep foundations.

Comments on the article 'Probabilistic Foundation Settlement on Spatially Random Soil,' by Gordon A. Fenton and D.V. Griffiths. Uncertainties in behavior of foundations; Use of a different finite element methodology.