bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ring Shrinkage Test for Expansive Clays: A Suggested Simple Test Method for Determining Vertical, Lateral, and Volumetric Shrinkage Potential
Authors: Hanafy EADE 
Published: February 2009

Abstract
The ring shrinkage test is proposed as a new soil testing method for expansive clays to describe quantitatively the soil shrinkage potential. The test provides direct measurements of the linear shrinkage in the form of vertical and lateral changes. In addition, the test provides an alternative test method for determining the shrinkage limit and volumetric shrinkage. The method requires undisturbed samples, and it utilizes the standard oedometer ring of consolidation testing equipment. Description of the proposed test method is presented including details of specimen preparation and data measurements.
Preparation Techniques for Oil-Sand Testing
Authors: Dusseault MB , Soderberg H , Sterne K 
Published: February 2009

Abstract
Evaluation of technologies for oil-sand mining and enhanced oil recovery in oil sands and other uncemented sandstone reservoirs requires high-quality undisturbed samples and special sampling, preparation, and testing techniques to minimize the effects of sample disturbance by expansion. This paper presents some methods developed for storage, preparation, and laboratory testing of the geomechanical properties of oil sands. These techniques have application to the handling of other earth materials that are difficult to prepare for testing.
Identification of Shales
Authors: Hopkins TC , Deen RC 
Published: February 2009

Abstract
Engineering tests were performed on 40 different types of shales. Both hard and soft shales, as well as shales having histories of embankment failures and shales having little known involvements, were tested. The suitability of ten different slake-durability test procedures was evaluated as a means of broadly characterizing the engineering performance of Kentucky shales. Two procedures devised during the study appeared to better characterize slake-durability properties than procedures previously proposed. Natural water contents and jar slake tests were performed to determine if such tests might provide a fairly rapid means of identifying troublesome shales. The natural water content of a shale was a strong indicator of the slake-durability properties. Swelling properties of ten shale types were examined. A good correlation was obtained between a newly devised slake-durability index and the water content of a shale after swelling was completed. When exposed to water, most of the shales exhibited high swell pressures.
Estimation of the Modulus of Elasticity of Cement Stabilized Materials
Authors: Kolias S , Williams RIT 
Published: February 2009

Abstract
A method of rapid estimation of the modulus of elasticity of cement stabilized materials from data that are usually available, without the need to resort to laboratory modulus determinations, is desirable especially for use in pavement analysis. This paper describes the derivation of a method for continuously graded materials, which is based on a single number grading index, that is, the gradation modulus, which can readily be calculated from the grading curve of the material to be stabilized. Another method derived empirically and based on the bulk density and optimum moisture content of the stabilized material is also presented. Predicting accuracy of the methods is compared with data available from the literature and is judged satisfactory for pavement analysis purposes.
Effects of Dust Suppressants on Tailing Sand Permeability
Authors: Scott JC 
Published: February 2009

Abstract
Permeability test results using tailing sand and six dust suppressants are presented. Dust suppressant dilution and application rates used were those recommended by the chemical manufacturers for tailing deposits. Each specimen was placed at a dry density of 15.6 kN/m3 (99.2 pcf) and a moisture content of 8% in standard U.S. Bureau of Reclamation (USBR) percolation cylinders. These initial conditions represented average values measured in tailing dam sand beaches.
The Theory of One-Dimensional Consolidation of Saturated Clays: III. Existing Testing Procedures and Analyses
Authors: Znidarcic D , Croce P , Pane V , Ko H-Y , Olsen HW , Schiffman RL 
Published: February 2009

Abstract
The successful calculation of the progress of consolidation requires that both the theory used to model the field problem and the material properties used by the theory must be appropriate and suitable. Thus the testing procedure must provide reliable and consistent information on the material behavior. Further, the test procedure must be accompanied by methods of analysis that will produce values of the material properties that are appropriate to the theory.
This paper presents a summary of the existing laboratory methods that are used to determine the consolidation properties of soils. Emphasis is placed on the analysis of the test data. It is shown that all the methods that are currently used contain inherent simplifying assumptions. These methods are restricted in their applicability to problems where linear or constant material properties or both are good approximations to real behavior.
The Centrifuge as a Research Tool
Authors: Cheney JA , Fragaszy RJ 
Published: February 2009

Abstract
The principal uses of the centrifuge in geotechnical research are discussed following a short historical review. The principle of centrifuge modeling is based upon the requirement of similarity by model and prototype. This requirement can be determined either by analysis of governing differential equations or by dimensional analysis and the theory of models. Verification of similarity may be established by direct comparison with full-scale objects (usually prohibitively expensive) or by comparison with model tests at other scales (modeling of models). Centrifuge tests can also provide data for verification of numerical models and for theorizing on the fundamental behavior of soil structures.
Drum Centrifuge for Geotechnical Research
Authors: Cheney JA , Fragaszy RJ , Schofield AN 
Published: February 2009

Abstract
The use of a drum centrifuge for geotechnical research is described. This type of centrifuge is distinguished by its ability to carry a payload around the entire circumference of a rotating drum. This allows the formation of “endless” slopes and gives the centrifuge a large capacity at very low cost. The design and construction of the centrifuge is described in detail. Also, the test procedures used to conduct slope stability experiments, including consolidation of a clay slurry, in-flight cutting of the slope, and both short- and long-term stability tests are discussed. Deviations from true similarity, between model and prototype are listed, including fluctuation in acceleration, variation in water content, and stress paths. Possible future uses of the drum centrifuge are presented.
Platform Orientation and Start-up Time During Centrifuge Testing
Authors: Bloomquist DG , Davidson JL , Townsend FC 
Published: February 2009

Abstract
Two techniques are introduced that improve the reliability of centrifuge testing of settling slurries. In the first, mechanical equipment modifications are described that allow a correct platform orientation to be achieved during flight. In the second, a simple mathematical equation is derived to account for the start-up period, during which the acceleration has not yet reached the final test level.
The Revised ASTM Standard on the Unified Classification System
Authors: Howard AK 
Published: February 2009

Abstract
ASTM Test Method for Classification of Soils for Engineering Purposes (D 2487) was significantly revised in 1983. The revisions require that soil is to be classified by using both a symbol and a name, and the group names were standardized. Organic silts and clays were redefined to recognize that organic soils occur that plot above the “A” line on the plasticity chart. More precise guidelines were established, particularly with regard to plasticity, so that only one particular classification will result. If boarderline classifications are used, the classification symbols are separated with a slash with the classification symbol indicated using the standard appearing first. Appendixes give example written descriptions, preparation of soil for testing, and guidelines for using the system for materials such as shale, mudstone, crushed rock, and slag
Development and Evaluation of Ultrasonic Piezoelectric Transducers for the Determination of Dynamic Young's Modulus of Triaxially Loaded Rock Cores
Authors: Howarth DF 
Published: February 2009

Abstract
Equipment has been developed that enables the rapid determination of dynamic Young's modulus of triaxially loaded rock cores. Measurement of dynamic modulus is based on a pulse propogation technique using piezoelectric transducers. A detailed description is given of the development of the equipment suitable for laboratory investigations. Details of a laboratory study investigating the variation between static and dynamic moduli of triaxially loaded rock cores are given.
A Scanning Device to Quantify Joint Surface Roughness
Authors: Lam TSK , Johnston IW 
Published: February 2009

Abstract
The shear strength characteristics of rock joints are highly dependent on the roughness of the joint surfaces. However, roughness is a relative term and current methods of describing roughness in quantitative terms are generally not suited to detailed analytical scrutiny. In connection with an investigation into the development of side shear resistance in rough rock socketed piles, a scanning device, which was automatic and free from operator subjectivity, was developed to provide detailed measurements of surface roughness of joint samples obtained in situ. The data collected were suitable for statistical analysis so that surface roughness could be uniquely quantified. The design and operation of the device is described, and an example of scanning is presented.
Resonant-Column Apparatus for Coarse-Grained Materials
Authors: Heiniger C , Studer JA 
Published: February 2009

AbstractTo investigate the low-strain dynamic properties of soils with grain size up to 25 mm (1 in.), a resonant column apparatus for specimens of 150 mm (6 in.) diameter and 450 mm (18 in.) height has been developed. Fine-grained materials can be tested using smaller specimens of at least 50 mm (2 in.) diameter. Compressive and torsional wave propagation at strains of the order of 10−4% and into the nonlinear range (up to approximately 5 × 10−2%) can be investigated at ambient air pressure up to 600 kPa (87 psi). Keeping the amplitude of excitation constant by means of an electronic feedback system, the specimen's resonant frequency and amplification can be found directly from the response curve by recording the amplitude ratio of accelerations at both ends of the specimen as a function of frequency. The equipment can be adapted to special research requirements or used to carry out routine measurements for scientific consulting.
Repeated Load Triaxial Testing of Frozen and Thawed Soils
Authors: Cole DM , Durell G , Chamberlain E 
Published: February 2009

Abstract
This paper describes the equipment and methodology used to determine the resilient properties of granular soils that exhibit thaw-weakening behavior. Such soils suffer a significant loss in stiffness as the result of freezing and thawing and subsequently experience an increase in stiffness during a recovery phase. The recovery phase results from gradual desaturation of the thawed soil and is characterized by an increase in the soil moisture tension level. We have developed a means to simulate this freeze-thaw-recovery process in the laboratory that calls for testing specimens several times at soil moisture tension levels corresponding to field observations.
We have designed test cells with removable bases to facilitate this sequential testing procedure. A given specimen remains on one cell base throughout the course of testing, thus avoiding excessive handling and allowing the material to remain in contact with a porous element built into the base. The porous element is part of a tensiometer system that continuously monitors the moisture tension level of the soil.
The cells are equipped with axial and radial displacement transducers and a load transducer, which, along with the other cell components, are assembled about each mounted specimen to be tested. All transducers are interchangeable between our larger and smaller triaxial cells. The cells receive 152.4-mm-diameter, 381-mm-long specimens and 50.8-mm-diameter, 127-mm-long specimens, respectively.
ASTM Geotextile Committee Testing Update
Authors: Suits LD , Carroll RG , Christopher BR 
Published: February 2009

Abstract
The use of geotextiles is a relatively new accepted concept in the field of geotechnical engineering. As a result there is a lack of standard procedures or test methods for evaluating the engineering properties or characteristics of geotextiles. ASTM Committee D-35 on Geotextiles and Related Products has evolved from two former subcommittees working jointly under two different Main Committees. This took place in the interest of accelerating the development of much needed test standards. The paper reviews the activities of Committee D-35 in the development of these standards. It also presents the authors' recommendations as to procedures to be followed until such time as these methods become accepted through ASTM. The basic procedures for the three standards that have been accepted and published as of the summer of 1985 are also presented.
Parameter Sensitivity of Hydraulic Conductivity Testing Procedure
Authors: Peirce JJ , Sallfors G , Peterson E 
Published: February 2009

Abstract
A methodology is presented that allows researchers to identify which parameters have the largest effect on key parameter(s), and thereby a priori direct investigations to concentrate on the most important area(s) of concern. Laboratory testing is often used in research to establish the effect of one or more parameters on one or more other parameters of concern. Because laboratory testing often is costly as well as time consuming, the number of tests in the laboratory necessarily must be limited. Therefore the effect of only a few parameters, sometimes only one, can be investigated. The choice of parameters to be studied is often made somewhat arbitrarily, and risks exist that the effect of an important parameter is overlooked.
The features of a ruggedness test are explained and its use is illustrated. A series of hydraulic conductivity tests are documented. Seven different parameters are varied in a total of eight tests to study their effects on the hydraulic conductivity. From the results it was possible to identify a select subset of parameters which have the greatest effect on the hydraulic conductivity: water content, lift thickness, and backpressure. Interaction between any two of these parameters, however, may produce confounding effects on the third. The method proved to be very effective and is suggested for application in other areas of investigation.
The Revised ASTM Standard on the Description and Identification of Soils (Visual-Manual Procedure)
Authors: Howard AK 
Published: February 2009

Abstract
ASTM Practice for Description and Identification of Soils (Visual-Manual Procedure) (D 2488) was significantly revised in 1984. Revisions were made to parallel the recent changes in ASTM Classification of Soils for Engineering Purposes (D 2487) and to reflect more of current practices used for visual-manual description and identification. Where possible, the number of terms for descriptive information (dry strength, moisture condition, and so forth) was reduced, and the criteria for deciding which term to use were made less subjective. Criteria for describing particle shape and for describing cementation of coarse-grained soils were added. Appendixes give example written descriptions, procedures for estimating particle size distribution, and guidelines for using the system for materials such as shale, mudstone, crushed rock, and slag.
Impact-Echo Response of Concrete Shafts
Authors: Lin Y , Sansalone M , Carino NJ 
Published: February 2009

Abstract
Numerical and experimental studies of the transient response of concrete shafts subjected to elastic impact were carried out using the finite element method and the impact-echo testing technique. Two- and three-dimensional finite element studies of concrete shafts were performed for: (a) solid shafts; (b) shafts containing cracks, voids, layers of low-quality concrete, and changes in cross section, such as bulges and necks; and (c) shafts in soil. These studies were carried out to gain an improved understanding of the impact response of concrete shafts containing flaws, problems for which there are currently no analytical solutions. It was also the intent of the numerical studies to determine whether information in addition to that obtained with existing nondestructive testing techniques could be obtained during impact testing of concrete shafts. Laboratory studies of solid concrete shafts were carried out to verify the finite element models. Subsequently, experimental studies were carried out on concrete shafts embedded in soil. These shafts contained flaws at known locations. The results of these studies show that additional information about the integrity of drilled shafts and piles can be obtained using impact techniques. The numerical studies also show that the finite element method is a powerful tool for studying the impact response of concrete foundation elements.
Hydrodynamic Aspects in the Rotating Clyinder Erosivity Test
Authors: Rohan K , Lefebvre G 
Published: February 2009

Abstract
A comparison of different experimental installations used to study clay erosivity is presented. Flow in a rotating cylinder used in geotechnical laboratories is studied in detail. Analysis of the shear stress is presented, and conclusions are drawn as to the limitations of the quantitative evaluations of the critical shear stress in the rotating cylinder test.
Simple Shear of an Undisturbed Soft Marine Clay in NGI and Torsional Shear Equipment
Authors: Talesnick M , Frydman S 
Published: February 2009

AbstractA series of undrained, simple shear tests were performed on undisturbed, soft, marine clay from the continental slope of Israel in a direct simple shear device (NGI) and in a new torsional shear apparatus. The new apparatus is described, and the problematics of simple shear testing in both devices are discussed. Most previous torsional shear testing on clays reported in the literature has been performed on remolded specimens. In order to prepare specimens from undisturbed samples of the soft, marine clay, whose natural moisture content is close to the liquid limit, a special preparation technique was developed. A comparison of the stress-strain curves obtained in the two devices indicates higher stiffness and strength of the specimens tested in the torsional equipment; a similar observation has been reported in the literature from tests on sands and remolded clays. It is the authors' view that the main cause for the discrepancy is flexibility of the confining membrane in the NGI equipment. In view of the relevance of simple shear conditions to actual field problems, it appears important to further clarify this difference and to establish an accepted method for simple shear testing in the laboratory.
Uniformity Tests in Calibration Chamber Samples by the Thermal Probe Method
Authors: Bellotti R , Ghionna VN , Morabito P 
Published: February 2009

Abstract
The calibration of geotechnical instruments for in-situ tests, performed on sand samples reconstituted in huge calibration chambers (CC), requires the reproduction of large specimens at given relative densities with good repeatability and satisfactory homogeneity. A test method has been developed with the purpose of evaluating the relative density, DR, in different locations of the CC samples without removing sand.
The method is based on experimental correlations between the density and the thermal conductivity of dry sand. The thermal conductivity is determined by small thermal probes, 1 mm in diameter and 70 mm in length, placed in different locations inside the calibration chamber before the pluvial deposition of the specimen. The homogeneity of the specimen is assessed by the local values of DR. A calibration procedure of the thermal probe is proposed that takes into account the effects of stresses on the thermal conductivity of the sand. Examples of uniformity tests performed in ENEL-CRIS and ISMES calibration chambers are presented.
Influence of Voids on Density Measurements of Granular Materials Using Gamma Radiation Techniques
Authors: Tan S-A , Fwa T-F 
Published: February 2009

Abstract
The use of gamma radiation equipment for the nondestructive measurement of soil density originated nearly four decades ago. The typical procedure involves a careful calibration of the gamma radiation counts on specimens of known density of the same materials as those whose density are to be measured. This paper presents the results of laboratory gamma-ray density measurements on 100-mm-diameter specimens with an adapted twin-probe transmission-type density gage originally developed for field use. Primary factors affecting density calibration for soils include soil composition and soil porosity. To appreciate the soil composition factor, 100-mm-diameter specimens of solid materials similar to the soil minerals were tested, and from the data a linear ln (COUNT) versus DENSITY calibration line for solid materials was obtained. Next, aluminium cylindrical specimens with concentric holes of various diameters representing various porosities from 0 to 90% were tested. When compared to the solid material calibration line, it is clear that the bulk density calculated based on the gamma-ray path geometry gives the same calibration as the solid specimens. Subsequently, cylindrical specimens of dry sands and gravels were also made and tested. Results indicate that specimens of uniform densities and uniform void distributions must be used for calibration. Subsequently, using the calibration line obtained for solid homogeneous specimens, densities of porous soils measured by the gamma-ray device would be the bulk density of the materials confined in the path geometry of the gamma rays. Thus the gamma-ray apparatus can be a very useful tool for identifying nonuniformities due to void variation within the same specimen.
Resonant Column Tests on Partially Saturated Sands
Authors: Qian X , Gray DH , Woods RD 
Published: February 2009

Abstract
This paper describes the measurement of the influence of capillary effects on the dynamic shear modulus of partially saturated sands. A Hall-type resonant column apparatus was used to perform the experiments. The materials tested included natural angular and subrounded sands, angular and subrounded sands with specified artificial gradations, and uniform angular and subrounded sands with various minus No. 400 sieve size fractions.
Capillary stresses can significantly increase the shear modulus of unsaturated sands. Void ratio, confining pressure, degree of saturation, grain shape, and grain-size distribution are the primary factors affecting the shear modulus of partially saturated sands.