bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Constant Normal Stiffness Direct Shear Device for Static and Cyclic Loading
Authors: Ooi LH , Carter JP 
Published: February 2009

Abstract
A device has been designed and built to carry out both static and cyclic direct shear tests on specimens of soil and rock and on interfaces of soil or rock and construction materials. The device has the special capability of allowing the shear deformation to proceed under conditions of constant normal stiffness. This is in contrast to the more conventional direct shear devices, which permit shearing under conditions of constant normal stress. It is expected that the constant normal stiffness conditions will be more representative of many in-situ conditions of shear deformation; an important example occurs at the interface of a pile and the formation in which it is placed (particularly those piles that are grouted into the formation). When used with a servo-controlled testing machine the device is capable of applying either static or cyclic shear loading to the test specimens utilizing either load or displacement control. The device is described in this paper, and typical results are presented for static and cyclic loading of a variety of interfaces including some that dilate on shearing and others that collapse as they are sheared.
Reproducibility of Borehole Shear Test Results in Marine Clay
Authors: Lutenegger AJ , Timian DA 
Published: February 2009

Abstract
An investigation was conducted to determine the variability of borehole shear test results obtained in testing soft and medium consistency marine clays. A statistical comparison of the results of stage tests obtained by different operators at two test depths at a research site is made. An additional comparison of the results obtained from stage tests and fresh shearing and a brief discussion of the linearity of both types of tests is also made. A short summary discussing the applicability of the results is also presented.
Suggested Method for Performing the Borehole Shear Test
Authors:   ASTM Subcommittee D18.02
Published: February 2009

Abstract
ASTM Committee D18.02 on Sampling and Related Field Testing for Soil Investigation (Mr. Ralph Brown, Chairman) suggested that this proposed suggested method be published herein to provide exposure and solicit comments for users. The purpose is to improve its clarity, accuracy, and acceptibility, so that in the future, Committee D18.02 may submit it for publication in the Annual Book of ASTM Standards. Suggestions for revision and other comments should be sent to Alan J. Lutenegger, Subcommittee D18.02.12. The subcommittee will fully consider all comments and suggestions that provide specific improvements to the proposed method.
Pressuremeter Creep Testing in Ice: Calibration and Test Procedures
Authors: Kjartanson BH , Shields DH , Domaschuk L 
Published: February 2009

Abstract
In situ pressuremeter creep tests of ice require that particular attention be paid to the precision with which the borehole diameter is measured because failure of ice often occurs at strains as small as 1%. Therefore, precision is important to obtain an accurate picture of the stress-strain-time response of the ice before failure. Also, the pressure applied to the ice must be known precisely since the creep rate varies as the cube of the stress. Thus, careful calibration of the pressuremeter is necessary.
This paper outlines how a monocellular pressuremeter equipped with an internal caliper should be calibrated to take into account freezing temperatures and the long duration of creep tests. The probe in question contains a two-arm caliper system which determines the diameter of the probe electromechanically; this system must be calibrated before each test. Secondly, both the thickness and resistance of the rubber membrane must be known at any stage of a test; both are dependent on temperature, internal probe pressure, displacement, and elapsed time. The paper also discusses preferred test procedures.
Axial Deformation Measurement in Repeated Load Triaxial Testing
Authors: Nataatmadja A , Parkin AK 
Published: February 2009

Abstract
This paper describes a method of axial deformation measurement for use in repeated load triaxial testing of pavement materials. An internal deformation measurement system is necessary because of the low strain regime involved, but normal transducers can only be used in an inert cell fluid. As this is both expensive and messy, the use of sealed transducers in water is preferable, but the cost of such units induces the use of a system based on a single transducer. Therefore, aluminium rings are used in an arrangement that allows the mean axial deformation over the central portion of the specimen to be determined by the use of a single hermetically sealed displacement transducer.
Statistical Description of Triaxial Shear Test Results
Authors: Schoenemann MR , Pyles MR 
Published: February 2009

Abstract
Any probabilistic approach to slope stability assessment requires an adequate statistical description of soil strength. Current statistical methods of strength description are unsuitable for this purpose. A statistical technique of soil strength description appropriate for the probabilistic assessment of slope stability in c′, φ′ soils under drained conditions is developed here. The technique is applied to a set of results from triaxial strength tests on residual soil materials. Techniques for assessing the adequacy of a statistical description are discussed.
Effects of Arching on Response Time of Miniature Pore Pressure Transducer in Clay
Authors: Kutter BL , Sathialingam N , Herrmann LR 
Published: February 2009

Abstract
A study of the response time of miniature pore pressure transducers embedded in clay soils is presented. The highly nonuniform pore pressure distributions around the transducers due to arching and stress concentration can have a significant effect on transducer response especially when the surrounding soil is loaded anisotropically. This is caused by the difference in compressibility of the soil and the transducer housing. Finite-element analysis and experimental results confirm the importance of these effects. A spherical porous stone or a cylindrical stone with top and side drainage results in significant reduction in response time and in overshoot due to arching effects.
Influence of Soil Structure on the Stress-Strain Behavior of Sand-Bentonite Mixtures
Authors: Wan AWL , Graham J , Gray MN 
Published: February 2009

Abstract
The influence of soil structure on the behavior of clay-rich mixtures has been examined. Mixtures of sand and bentonite, known as buffer, have been studied to determine their suitability for nuclear fuel waste containment. Triaxial tests have been performed on compacted specimens to determine the strength and constitutive behavior of the buffer. Two techniques were followed in preparing specimens. In the first method, specimens were compacted to dry densities of 1.5 Mg/m3 and 28% moisture content and were allowed to equilibrate to their confining pressures prior to test. The second method, which aimed at shortening the test durations, involved forming specimens at dry densities corresponding to equilibrium states at the test pressure levels. This required compacting sand-bentonite mixtures at different densities and moisture contents.
The study indicates that the compressibility and stress-strain behavior of the buffer are strongly influenced by specimen preparation techniques. Because of the different degrees of soil manipulation and moulding moisture contents, the specimens had different macrostructures. This affected the swelling and shear behavior of the buffer. However, preyield porewater pressure response and ultimate shear resistance appeared to be unaffected by preparation techniques. Shear test results suggest that the buffer is anisotropic and slightly strain softening in shear. An ultimate strength envelope of c' = 0 kPa and φ' = 14° is determined in the pressure range of 0 to 1.5 MPa.
Frequency Response of Diaphragm Pore Pressure Transducers in Dynamic Centrifuge Model Tests
Authors: Lee F-H 
Published: February 2009

Abstract
A theoretical relation for estimating the frequency response of diaphragm pore pressure transducers is derived by considering the interaction between the diaphragm, porous cap, air, and pore fluid inside the transducer. Using this relation, the frequency response of a pore pressure transducer under several centrifuge modeling environments is studied. The results indicate that the viscous drag imposed by the porous cap on the pore fluid can significantly reduce the sensitivity of the transducer to high frequency pore pressure fluctuation. This may impair the accuracy of dynamic pore pressure measurements in high-g centrifuge modeling of dynamic events if viscosity scaling is used.
Measuring Strains in Buried Flexible Pipes
Authors: Moore CA , Donaldson CF 
Published: February 2009

Abstract
A field measurement system is described for determining strains in buried flexible pipes. The microprocessor-based system obtains data that is subsequently analyzed on minicomputers or mainframe machines. The field system is also capable of analyzing the data using its own microprocessor provided that a graphics terminal is available. Numerical algorithms for analyzing the data are developed, and typical results are presented.
Preparation of Grouted Sand Specimens for Dynamic Testing
Authors: Chang T-S , Woods RD , Li NH 
Published: February 2009

Abstract
Improvement of soil properties by means of chemical grouting, cement grouting, and cement/fly ash stabilization has been widely used in practical geotechnical applications. Knowledge of dynamic behavior of cemented soil is essential for seismic research and design. A laboratory testing program is conducted for determining the low-strain dynamic properties of artificially cemented soils. The major significances of this research are: 1. Focusing on the effect of confining pressure because confining pressure is one of the most important factors affecting the dynamic properties of cemented soils and directly implies the in-situ depth of soil, which is also significant in a practical grouting project. 2. Defining the “degree of cementation” as a percentage of void space between soil particles occupied by cementing material instead of the percent weight of cementing material to total weight of the soil to be cemented as normally used in previous research. Degree of cementation by volume as defined in this study gives clearer description regarding the soil-cement-void interaction of a cemented sand. 3. Using various types of cementing materials and soils to cover sufficient range of parameters involved in the study. 4. Two methods for preparing cemented sand specimens are developed in compliance with the methods practically used in the field for the testing materials selected in the study (injection method and “mix-compact” method).
Statistical Evaluation of Bangkok Clay Shear Strength Parameters
Authors: Ali MM 
Published: February 2009

Abstract
All natural soils show some variation in properties due to the inherent variation in composition and consistency during formation or to the differences in testing techniques and the methods used to analyze a given set of test results. A statistical approach to the evaluation of the measured parameters offers a means to define these variabilities by providing a basis to quantify the reliability involved in the analysis. This paper presents a statistical study for the evaluation of shear strength parameters (c, Φ, ¯c, ¯Φ, Af) for Bangkok clay and makes a comparison with previous findings for this material.
The results obtained show that the variations of strength parameters can be approximated by a Beta I distribution function. The accuracy in estimating the distribution parameters depends on the number of observations. In an actual sampling there are relatively few specimens and the true mean can be estimated with some confidence limits by means of statistical analysis.
Suction-Moisture Content Calibration of Filter Papers from Different Boxes
Authors: Sibley JW , Smyth GK , Williams DJ 
Published: February 2009

Abstract
The filter paper method is probably the simplest of the methods available for estimating the suction of a clay soil. The method measures soil suction indirectly by simply measuring the moisture content of a filter paper having been brought to the same suction as the soil. Calibration of representative specimens of the filter paper over a range of known suctions defines the suction-moisture content characteristic of the material. The calibration must be carried out in a closely temperature-controlled environment using various apparatus depending on the particular level of suction. There have been a number of impediments to the wider application of the filter paper method. One of these is the need to have access to a closely temperature-controlled laboratory with a range of specialist calibration apparatus. This difficulty has been exacerbated by the belief that to account for the possible variability of filter papers between boxes, even from the same production batch, representative specimens from each box require separate calibration. Based on the results of careful calibration and subsequent analysis, it appears that, provided the boxes are all from the same production batch and are purchased from the same outlet at the same time, the calibration of only one box is necessary.
Influence of Storage and Reconsolidation Procedures on Clay Properties
Authors: Graham J , Jamieson MR , Ho DY-F , Azizi F 
Published: February 2009

Abstract
The delay between sampling and testing of clay specimens and the control kept over their volumes during storage are known to affect the strengths and compressibilities subsequently measured in the laboratory. The measured properties are also affected by reconsolidation procedures. This paper deals with reconstituted specimens of illite stored for fixed periods of up to one week, reconsolidated using three different procedures, and then sheared undrained. Results are compared for overconsolidated specimens (OCR = 2) prepared with Koc = 0.53 or 1.0. The paper provides qualitative evidence for the well-known result that the best recovery of stress-strain behavior is obtained from specimens stored at constant volume (undrained) for as short a time as possible and then reconsolidated to their in-ground stress state before shearing. Providing this is done, results suggest that undrained strengths su and Af-values should be recoverable with an accuracy of about ±5 to 6%. Much larger differences can be expected in the relative stiffness E50/su.
An Experimental Laboratory Facility for Studying Shock-Induced Liquefaction
Authors: Veyera GE , Charlie WA 
Published: February 2009

Abstract
Our paper describes a new experimental laboratory apparatus developed to investigate the transient and long-term porewater pressure response of saturated soils subject to compressional stress wave loading. An overview of the laboratory system, the various components, and the experimental procedure followed are presented. Measurements include porewater pressure-time histories for the specimen and total stress time histories for the applied load. Test results indicate that Monterey No. 0/30 sand can be liquefied even at high initial densities and effective stresses under undrained, one-dimensional, confined compressive shock loadings.
Simplified Heave Prediction Model for Expansive Shale
Authors: Dhowian AW 
Published: February 2009

Abstract
A model is suggested to predict heave of expansive shale formation based on soil suction change. The model satisfactorily described the field volume change where the anticipated heave is compared with direct measurement obtained from an instrumented field station. The prediction is further simplified by introducing a model that only uses the moisture content variation to determine the amount of heave. Close agreement is observed between measured and model-predicted shale behavior. Application of this simplified model eliminates the difficulty of recovering an undisturbed specimen of shale which is highly weathered and friable as well as laminated.
Determination of Design Parameters of a Mesh-Type Soil Reinforcement
Authors: Lo S-CR 
Published: February 2009

Abstract
Problems in determining design parameters of a new mesh-type soil reinforcement are investigated. A special apparatus referred to as the split-box was developed to enable measurement of design parameters with large-scale laboratory tests. In addition to the scale of the tests, the design innovations of the split-box ensure reliability of test results, as verified by a number of calibration tests. Test data are highly consistent and support the relevance of conducting tests with the split-box.
Effects of Imperfect Fixity in Spring-Top Resonant Column Tests
Authors: Min T , Drnevich VP , Wang J 
Published: February 2009

Abstract
A two-degree-of-freedom model is proposed to study the effects of imperfect fixity at the active end of the spring-top resonant column apparatus. A computer program using the SYMPHONY spreadsheet is developed to calculate the dimensionless frequency, F, from which the modulus can be determined. It is found that the effect of reaction mass through the parameter, Tr; on dimensionless frequency, F, cannot be ignored if Tr &lt; 20. As the ratio of mass attached to the active end of the specimen to specimen mass, T0, increases, the variation of F increases. When Tr ≥ 20, the effect of T0 becomes small. It is recommended that Tr be greater than 20 if the single-degree-of-freedom model is used to determine modulus of soil. It also is found that damping ratios of specimen and apparatus do not strongly affect the dimensionless frequency, F.
Procedures for Prediction of Dynamic Lateral Pile Group Response in Clay from Single Pile Tests
Authors: Blaney GW , O'Neill MW 
Published: February 2009

Abstract
The design of pile foundations for dynamic lateral loads is significant in the design of both offshore and onshore structures subject to vibratory loads and earthquake motion. Sophisticated numerical models are available for predicting the response of these foundations; however, simple and cost-effective methods are needed to confirm the analysis results and improve the understanding of the overall system behavior. A field testing procedure consisting of slow cyclic load tests and plucking tests is suggested and integrated with simplified single-degree-of-freedom and modal analyses of the test results to produce response functions for dynamic design. The technique is particularly attractive because the field tests may be performed quickly and economically on a test pile or piles installed at the site to determine bearing capacity and/or drivability. The proposed test and analyses procedures were applied to a single pile and nine-pile group installed in stiff clay and tested at the University of Houston pile test facility, and the results are compared favorably with more detailed response information published previously. A good approximation of the pile group dynamic behavior was obtained from the simplified single pile response analysis.
A Cohesive Soil for Large-Size Laboratory Deposits
Authors: McManus KJ , Kulhawy FH 
Published: February 2009

Abstract
The preparation of high-quality, large-size cohesive soil deposits is possible using the slurry method and is practicable if a suitable soil material is used. The requirements for such a soil are discussed and the results of a survey of available ingredient materials presented. A testing program of six trial soil mixtures is described, including consolidation of slurry in a special apparatus. Each trial soil is evaluated, and detailed properties of the selected material, called Cornell clay, are presented. The results from a series of CIUC triaxial tests show that Cornell clay has normalized strength parameters similar to many naturally occurring cohesive soils. Supply sources for the ingredient materials are given.
A Method for Determining the Surface Area of Quarried Rocks
Authors: Garga VK , Townsend R , Hansen D 
Published: February 2009

Abstract
A coating method which used nickel powder to determine the surface area of angular rock particles was found to be reproducible and required no special equipment. The technique utilized the difference in weight between uncoated and coated rock particles. Four calibration methods were considered. Relationships between surface area and an estimate of the volume of individual rocks were obtained for graded rock having a mean diameter of 25.6 mm and for unisized rock having a mean diameter of 130 mm. The volume of each rock was estimated by measuring the three orthogonal axes of each rock. An analysis of covariance showed that whether or not a rock was spheroid in shape was statistically significant for the evaluation of surface area. Curves relating the hydraulic mean radius to porosity for a range of unisized rock sizes are presented. A procedure for estimating the hydraulic mean radius for a graded media is also discussed.
Sample Size for Laboratory Calibration of Subsurface Neutron Moisture Gauges
Authors: Morris PH , Williams DJ 
Published: February 2009

Abstract
The estimation of adequate sample size is critical to all laboratory methods of calibration of neutron moisture gauges. Neutron gauge response is a function of the true sample geometry rather than an arbitrarily defined spherical geometry. A two-group solution is obtained for neutron flux in a homogeneous, finite, cylindrical sample. The theoretical flux distributions for this solution and for infinite and spherical samples are compared for three representative media. The results show that significant reductions of sample size are possible for media with low moisture contents if the true cylindrical geometry is considered.
Small Diameter Piston Sampling with Cone Penetrometer Equipment
Authors: Kay JN 
Published: February 2009

Abstract
A small diameter piston sampler that can be operated by a cone penetrometer rig has been developed specifically for recovery of sand and clay samples under conditions where sample recovery using ordinary means is difficult. The 22-mm-diameter sample that is recovered in a polythene sheath is valuable for visual examination of the soil rather than for most laboratory testing purposes. Provided the soils are penetrable, the sampler may be pushed to any desired depth before the sampling operation; then the central 12-mm-diameter rod in the drill stem is held stationary while the sampling operation takes place. In initial tests when applied to soft, wet, interlayered sands and clays that could not be recovered in open tubes, essentially 100% recovery was obtained.
Measurements of Strength Parameters of Concrete-Rock Contact at the Dam-Foundation Interface
Authors: Lo KY , Ogawa T , Lukajic B , Dupak DD 
Published: February 2009

Abstract
A long-term dam safety program has been initiated by Ontario Hydro to evaluate the safety of existing dams. Most of the dams in operation were constructed between 1910 and 1975. The larger dams are often of the concrete gravity type founded on rock.
As an integral part of this program, laboratory methods for the measurement of the complete strength envelope of bonded concrete-rock contact and strength parameters of unbonded contact have been developed. The principal method and interpretation of each type of test are described in this paper. Typical results of tests on samples of dam-foundation interface recovered from existing dams are presented. The methods developed enable the determination of the strength envelope appropriate for the working stress level during operation of dams and the direct measurement of tensile strength and cohesion, thus removing the uncertainty of extrapolation for the cohesion component of strength in conventional triaxial and direct shear tests.