bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laboratory Properties of a Soft Marine Clay Reinforced with Woven and Nonwoven Geotextiles
Authors: Indraratna B , Satkunaseelan KS , Rasul MG 
Published: February 2009

Abstract
This paper is concerned with the laboratory properties of a geotextile-reinforced compacted soft marine deposit with respect to its compaction, compressive strength, and time-dependent settlement characteristics. Two different geotextiles, namely, Polyfelt TS-500 (nonwoven) and Cardon SG PP 150 (woven) have been investigated. It was observed from the experimental study that a nonwoven geotextile contributes very differently as compared to a woven geotextile when placed within soft clay soils. This is because of the fact that the nonwoven Polyfelt fabric allows better drainage (dissipation of pore pressures) in comparison with the woven Cardon geotextile, particularly at high moisture contents. The compactibility of the reinforced sample is affected by the moisture content, number of fabric layers, and the type of geotextile. With the presence of geotextiles, the compressive strength of the soil is dictated not only by the internal mode of failure induced in the samples, but also by the spacing and the drainage capacity of the geotextile layers.
Computer-Aided Pressuremeter Tests
Authors: Law KT 
Published: February 2009

Abstract
A completely portable computer-controlled servo-mechanism designed for use with the Cambridge self-boring pressuremeter consists of a computer, a data acquisition system (DAS), and an electric-to-pneumatic (E/P) transducer. The computer obtains information on the current state of a test through the DAS and determines the next step in accordance with prescribed test conditions. An appropriate voltage is then sent to the E/P transducer, which regulates in proportion to the voltage received the pressure for expanding the pressuremeter. At present, four test conditions are programmed: a controlled stress increment test, a controlled strain rate test, a controlled strain test, and a cyclic test. Experience with different soils shows that the mechanism operates to design specifications.
Permeability Testing in the Triaxial Cell
Authors: Carpenter GW , Stephenson RW 
Published: February 2009

AbstractIt has been suggested that a triaxial shear test chamber can be used to measure the permeability of low permeability soils. To verify this, the influence of a number of test parameters on the measured coefficient of permeability was investigated. Results indicate such permeability tests should be performed on samples having a minimum diameter of 71.1 mm (2.8 in.) and a length to diameter ratio of 0.5 to 1.0. It was found that a permeant consisting of 1 g of magnesium sulfate heptahydrate (epsom salt) dissolved in 1 L of deaired, distilled water is adequate for general permeability testing. The triaxial, falling head permeability test should be conducted at a gradient that results in an applied effective stress at the outflow end of the sample less than the preconsolidation stress of the material. It was found that with very careful trimming, the influence of the smear zones created at the ends of the samples during the trimming process can be minimized.
Experimental Study of Rheological Properties of a Sand Using a Special Triaxial Apparatus
Authors: Bouvard D , Stutz P 
Published: February 2009

Abstract
A special triaxial apparatus allowing for a gammametric measurement of local density is used to study the influence of experimental conditions in triaxial tests. Compression tests performed along different stress paths and classical extension tests provide reliable results on the rheological behavior of sand up to large strains and permit characterization of the limit state of perfect plasticity.
Swelling Pressure of Clays
Authors: Sridharan A , Rao AS , Sivapullaiah PV 
Published: February 2009

Abstract
Experiments by three methods to determine the swelling pressure of clays showed that the conventional consolidation test gives an upper bound value, the method of equilibrium void ratios for various consolidation pressures gives the least value, and tests by the constant volume method give intermediate values. However there is no definite relationship between the three methods. The paper also shows that time effects involved in conducting the tests and the effect of stress path are both significant. Time versus swelling, and to a greater extent, time versus pressure relations can be represented by a rectangular hyperbola, which can be used to predict the ultimate swelling and the swelling pressure, respectively.
Tests with varying initial conditions of molding moisture content and density have exhibited a unique relationship between swelling pressure and the initial dry density for black cotton soil. This result is in line with the osmotic pressure theory. The molding water content has marginal effect on the swelling pressure.
The Application of Multivariate Statistics and Saturation Extract Data to Identify Dispersive Clay Soils
Authors: Craft D 
Published: February 2009

Abstract
Soils from a geotechnical project in Oklahoma may be classified as dispersive or nondispersive with a high degree of confidence by substituting selected pore-water data (weight percent H2O at saturation, saturation extract pH, log base 10 of the pore-water conductivity, and log base 10 of the pore-water sodium concentration) into derived discriminant classification functions. The discriminant functions were derived using discriminant analysis, a multivariate statistical classification technique, performed on a 28-sample data set. This statistical procedure was utilized after problems were noted with the currently accepted porewater chemical test for dispersion, suggested by Sherard et al. Suggestions for using the derived discriminant function as the basis of a simple chemical field test and precautions regarding data interpretation are presented.
Estimating Liquefaction Potential of Sands Using the Flat Plate Dilatometer
Authors: Robertson PK , Campanella RG 
Published: February 2009

Abstract
A new flat plate dilatometer test (DMT) based method for liquefaction assessment of sand is presented. Field and laboratory data from a site near Vancouver, British Columbia, Canada are presented to provide a preliminary evaluation of the proposed DMT based liquefaction assessment method.
Effect of Cementation on the Cone Penetration Resistance of Sand: A Model Study
Authors: Rad NS , Tumay MT 
Published: February 2009

Abstract
A laboratory study was conducted to investigate the effect of cementation on the cone penetration resistance of sand. A new apparatus to form homogeneous artificially cemented sand specimens as well as uncemented ones, and a miniature quasi-static cone penetrometer were developed. Artificially cemented specimens with 1 and 2% cement content and relative densities ranging from 18 to 80% were tested. The penetration resistance of the cemented specimens was compared with those of comparable uncemented specimens. The influence of cement content and relative density of the specimens on their quasi-static cone penetration resistance was studied. The results indicate that cementation has a pronounced effect on the penetration resistance of sand.
Triaxial Equipment for Permeability Testing with Hazardous and Toxic Permeants
Authors: Evans JC , Fang H-Y 
Published: February 2009

Abstract
The measurement of the hydraulic conductivity of finegrained soils utilizing hazardous and toxic permeants requires equipment speciffically designed and constructed for that purpose. Interaction between the pore fluids in the soils and the resulting soil response must be considered as well as the compatibility between the test equipment and the permeants. Further, a method of modeling the state of stress and permeation relative to field conditions must be incorporated in order to arrive at a system that can adequately determine the effects of hazardous and toxic permeants upon the hydraulic conductivity of fine-grained soils.
The testing system developed for hydraulic conductivity testing with hazardous and toxic permeants has three major components. These are the control panel, the permeability board, and the triaxial cell. The necessary strength and compatibility was accomplished through the optimum use of stainless steel and aluminum to provide adequate rigidity while providing the ultimate compatibility through the use of Teflon® at any points in which the permeameter is in contact with the permeant. Equipment design and fabrication considerations in their special applicability for testing of hazardous and toxic permeants are discussed in this paper.
Procedure for a Rod Shear Test
Authors: Felio GY , Briaud J-L 
Published: February 2009

Abstract
A laboratory instrument, called the rod shear device, was developed to measure the shear transfer characteristics of a model pile inserted into a clay sample. The apparatus was designed to accommodate soil samples recovered from field investigations without extruding the specimen from its sampling tube and thus avoiding disturbance caused by stress relief and handling. A rod shear testing procedure is recommended for monotonic and cyclic loading tests. Typical results are presented.
Preparation of Specimens of Noncohesive Material for Mercury Intrusion Porosimetry
Authors: Juang CH , Holtz RD 
Published: February 2009

Abstract
This technical note describes a technique for the preparation of test specimens of compacted noncohesive granular material for mercury intrusion porosimetry (MIP) tests without altering or destroying the soil fabric. The technique makes it possible to measure and determine pore-size distribution (PSD) of the noncohesive soils by a standard MIP test method (for example, ASTM Test Method for Determination of the Pore Volume Distribution of Soil and Rock by Mercury Intrusion Porosimetry [D 4404]).
The technique involves use of a powdered phenolic resin. First, dry sand was mixed with a small amount of powdered resin (0.5% of dry weight of the sand) before compaction. After compaction, the sample along with compaction mold was placed in the oven at 170°C for 1 h. The melted resin acts as a glue to bond the sand grains together. Then the sample was removed from the oven, and the MIP specimens were trimmed from the resin-bonded sample. The results of repeated MIP tests on multiple specimens trimmed from resin-bonded compacted samples were very reproducible, which indicates that the proposed technique is a satisfactory way of preparing a noncohesive specimen for MIP tests.
Liquid Limit of Montmorillonite Soils
Authors: Sridharan A , Rao SM , Murthy NS 
Published: February 2009

Abstract
The present work investigates the influence of compositional factors on the liquid limit of montmorillonite soils. The results showed that the percent clay fraction and surface area values did not relate with the liquid limit of the soils; the latter, however, were essentially controlled by the diffuse double layer thickness. Examination of the relations between compositional factors that affect the double layer thickness and liquid limit showed that the latter did not have a significant bearing with cation exchange capacity, while a near perfect correlation was obtained with the amount of exchangeable sodium ions present. Such a dependence resulted because of the greater ease of dissociation of adsorbed sodium ions from the clay surface in presence of water and subsequent contribution to the double layer thickness; the other exchangeable cations, namely, calcium, magnesium, and potassium, were strongly adsorbed by the clay surface and did not contribute appreciably to the double layer thickness.
A Rapid Method to Identify Clay Type in Soils By the Free-Swell Technique
Authors: Sridharan A , Rao SM , Murthy NS 
Published: February 2009

Abstract
This paper reports a rapid method to identify the presence of nonswelling clay, swelling clay, or a mixture of the two types of clays in a soil from the sediment volumes occupied by 10 g of dry soil in 100 mL of water and carbon tetrachloride, respectively, under no external constraint. Soils that occupy a sediment volume of &lt; 1.50 m3/Mg in water and 1.10 to 3.00 m3/Mg in carbon tetrachloride contain nonswelling clay. Soils that occupy sediment volume of ≤ 1.10 m3/Mg in carbon tetrachloride and a volume ≥ 1.50 m3/Mg in water contain swelling clay. Soils that occupy sediment volumes &gt; 1.10 m3/Mg in carbon tetrachloride and volumes ≥ 1.50 m3/Mg in water contain both nonswelling and swelling clays. The results agree well with X-ray diffraction and infrared analysis.
In the latter part of the work, the limitations in the existing definition of the free-swell index of soils is brought out. The present definition gives a negative free-swell value for soils containing nonswelling clay and a reduced value for soils containing a mixture of nonswelling and swelling clays. The free-swell index of soils is defined as the sediment volume occupied by 10 g of dry soil in 100 mL of water under no external constraint and expressed in units of m3/Mg. Further, the sediment volume of a soil (10 g) in a nonpolar solvent, is utilized to give information on the clay type present in the soil, namely, nonswelling, swelling, or a combination of both. A classification for identifying a soil's expansivity based on the new definition of the free-swell index and the clay mineralogical composition of the soils is given.
Cyclic Simple Shear Testing of Granular Materials
Authors: Shaw P , Brown SF 
Published: February 2009

Abstract
Developments to a pneumatically operated simple shear apparatus for dry granular materials allowing application of cyclic shear and normal stresses are described. Boundary transducers were of only limited success for stress measurement so a prediction method for complete description of the stress state was used. Tests on uniform crushed limestone of 1.5- and 3-mm nominal sizes showed that increased volumetric strains were developed under cyclic normal stress and bidirectional shearing. Shear strains were not much influenced by cyclic application of the normal stress.
A Monte Carlo Investigation of a Proposed Screen for NX-Borehole Jack Data
Authors: Axelrod MC , Verrill SP , Patrick WC , Yow JL 
Published: February 2009

Abstract
Heuze has submitted a draft standard guide to the ASTM Subcommittee D18.12 on Rocks and Soils for using the NX-borehole (“Goodman”) jack and calculating the in-situ deformation modulus of rock masses. One aspect of the proposed standard is a “data screen” based on a full platen seating criterion. This article describes a computer simulation study that was performed to test the effect of the screen on the modulus estimate. The study demonstrates that the screen can actually degrade the quality of the estimate. It is concluded that the section of the proposed standard guide that deals with the screening of data should not be adopted.
Compressibility Properties of a Horticultural Peat
Authors: Morin P 
Published: February 2009

AbstractThe compressibility of a typical horticultural peat has been studied in the laboratory. Compressibility is an important factor in the processing of this material since volume governs the cost of shipping. The final reconstituted volume and the appearance of the peat after shipping must also be taken into account for marketing. Compression tests have been carried out on a horticultural peat from Newfoundland. Simple equations relating initial water content, relative volume change, and vertical applied pressure are proposed. A fluff factor has been defined, and it was found to decrease with the maximum applied pressure. Finally the results obtained in the laboratory are applied to storage and processing examples that are encountered in the horticultural peat industry.
The Measurement of Gas Bubble Size Distributions in a Three Phase Laboratory Gassy Soil
Authors: Gardner TN , Goringe MJ 
Published: February 2009

Abstract
The technique developed can be used to measure the total void, gas void, or particle size distribution in both gassy and saturated sediments provided the void spaces, or particles, can be approximated to spheres. Here the technique is demonstrated for measuring gas bubble size distribution in a reconstituted estuarine silty clay, which has been impregnated with methane gas using the method described by Nagaswaran. The process involves specimen preparation of a resin impregnated specimen to provide images using a scanning electron microscope (SEM). An average planar size distribution is obtained from the SEM images by computerized measurement of pixels on a monitor distinguished by luminance intensity phasing. Conversion from the planar to a spherical size distribution is carried out by a statistical method of probability. Results are presented that illustrate the consistency and accuracy of the measurement technique as a whole. Observations are made regarding the structure of the laboratory gassy soil which may be relevant to an in-situ sea bed gassy soil.
Assessment of the Unconfined Compressive Strength of a Lime Stabilized Soil by an Abrasion Test
Authors: Arabi M , Delpak R , Wild S 
Published: February 2009

Abstract
Stabilization by lime, which is frequently carried out to improve the mechanical properties of soils, results from the formation and development of cementitious calcium silicate aluminate hydrate gel. The gel produces interlocking and bonding of the soil particles, hence increasing the strength and abrasion resistance. The proposed method to assess the compressive strength of the existing structure of lime stabilized soil using a simple mechanical abrasion technique, provides an alternative means by which the strength characteristics can be assessed. The advantages of employing the abrasion method are (1) the relative ease of specimen collection and preparation as the test is not particularly sensitive to specimen size and shape and (2) the ease of application to existing structures as large-scale mechanical testing equipment would not be required once a calibration chart has been established, and testing could be carried out on site.
Removal of Cementation Bonds in Stressed Overconsolidated Clays
Authors: Griffiths FJ , Joshi RC , Nagaraj TS 
Published: February 2009

Abstract
Soils develop cementation during and after formation because of the effects of stress, time, and environment. The effects of cement removal on the change of state of soil under stress are discussed in this paper. The change in the state of stiff, overconsolidated, cemented clay under stress is reflected by void ratio change when the cementation bonds are removed. The observed increases in void ratio have been attributed to the latent physico-chemical behavior of the clay. The consolidation process is restrained during both deposition and subsequent stress history once clays are cemented. Upon further loading, clays with cement bonds removed follow the e-log σ paths predicted for the uncemented state of the same soil both for normally and overconsolidated stress conditions.
Effects of Borehole Fluid on Standard Penetration Test Results
Authors: Seed RB , Harder LF , Youd TL 
Published: February 2009

Abstract
The standard penetration test (SPT) represents the most widely used in-situ test method for evaluating the liquefaction resistance of saturated soils. Significant progress has been made in recent years in developing correlations between SPT results obtained using different test procedures and equipment in order to develop a higher degree of standardization for SPT testing. One of the heretofore unresolved factors affecting SPT results is the effect of borehole fluid type (for example, water or drilling mud). This paper presents a study in which field data were obtained from SPT performed in adjacent boreholes, some filled with water and others filled with drilling mud, at four different sites in order to investigate this effect. A total of 213 SPT were considered: 147 SPT in mud-filled boreholes and 66 SPT in water-filled boreholes. Borehole fluid type (drilling mud versus water) was found to have no significant effect on STP resistances measured so long as careful and appropriate drilling and sampling procedures are employed.
Automatic Volume Change and Pressure Measurement Devices for Triaxial Testing of Soils
Authors: Lade PV 
Published: February 2009

Abstract
Desirable requirements for volume capacity and precision of volume change devices for triaxial testing are studied, and operational requirements for devices suitable for automatic datalogging are reviewed. Two devices that fulfill these requirements have been constructed by the writer by combining existing design principles. One device consists of a buret system with differential pressure measurements, and the other device operates on the principle of a double acting piston in which rolling diaphragms and a displacement transducer are the main components. In addition to their ability to measure volume changes, each device is outfitted with a pressure transducer and valves to provide all necessary means for performance and measurements required for (CD) and (CU) tests.
A New Simple Shear Apparatus
Authors: Budhu M 
Published: February 2009

Abstract
A new simple shear device capable of measuring a complete set of stresses during simple shear deformation is described. This simple shear device tests a cuboidal specimen whose lateral sides are surrounded by a rubber membrane reinforced by a stack of Teflon® coated aluminum plates. One of the aluminum plates is used as a transducer to determine the lateral stresses on planes normal and parallel to the direction of shearing. A load cell located around the middle of the top boundary provides data to deduce the normal and shear stresses as well as the pore-water pressures.
A sample set of results are presented to illustrate some of the advantages of this new simple shear device. The advantages include the ease of specimen preparation, the determination of the stress invariants, the pore-water pressures at the center of the sample, and the rotation of the principal axes of strain and stresses on a routine basis.
Prevention of Sample Deterioration
Authors: Brown PT , Chow JC-P 
Published: February 2009

Abstract
A series of unconsolidated undrained triaxial compression tests was carried out on specimens of reconstituted kaolin to determine the effects on modulus and strength of two different methods of sample storage after unloading. These results are compared with the values obtained when no unloading occurs, and when unloading is followed immediately by testing. It is seen that use of a simple sample compressor to restore the in-situ vertical effective stress in the specimen is very successful in reducing the deterioration of samples between unloading and testing.
Laboratory Measurement of Small Strain Shear Modulus Under K Conditions
Authors: Thomann TG , Hryciw RD 
Published: February 2009

Abstract
A new device to measure the small strain shear modulus (Gmax) under a no lateral strain condition has been developed. The techniques for measuring Gmax are discussed, with emphasis on bender element techniques. The performance of the bender elements are compared with results from simultaneous resonant column tests. An in-depth description of the lateral stress measurement system, the Gmax determination technique, and the measurement of vertical strain is presented along with representative test results to demonstrate the performance of the device.