bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some Effects of Test Configuration on Measured Soil Properties Under Cyclic Loading
Authors: Pyke R 
Published: December 2008

Abstract
The effects on soil properties measured under cyclic loading of some of the differences between the stress and deformation conditions in cyclic simple shear tests and cyclic triaxial tests are discussed. The importance of differences in the deformation conditions is emphasized. An approximate method is presented for computing the equivalent linear shear modulus of a cross-anisotropic triaxial test specimen. Experimental data on the properties of Monterey No. 0 sand measured in cyclic simple shear and cyclic triaxial tests are presented, and it is shown that in spite of some difficulties caused by the nonlinear behavior of the test specimens it was possible to obtain good agreement between the results of the two types of test.
Dielectric Constant Determination of Soils at L Band Microwave Frequencies
Authors: Okrasinski TA , Koerner RM , Lord AE 
Published: December 2008

Abstract
The use of microwaves as a nondestructive testing method for penetrating the ground and detecting subsurface details and anomalies is currently receiving active consideration. All variations of the technique require knowledge of the dielectric constant of the soil being penetrated by the microwaves. This paper presents a method for determining the dielectric constant of soils under various density and moisture conditions at L band frequencies, namely, 0.39 to 1.5 GHz. Using a technique based on open wire transmission line theory it was found that: 1. Dielectric constant decreases linearly as porosity increases. 2. Dielectric constant increases rapidly as moisture content increases. 3. Dielectric constant is soil type-dependent. 4. Microwave properties in soils are conveniently related to volumetric water content, a term which includes both porosity and water content characteristics. 5. Temperatures above freezing have little effect on dielectric constant. 6. The open wire transmission line test is convenient, rapid, and easy to perform for remolded soils in the laboratory.
A Modified California Bearing Ratio Test for Granular Materials
Authors: Livneh M , Greenstein J 
Published: December 2008

Abstract
It is known that laboratory and field tests, under saturation conditions, yield different California Bearing Ratio (CBR) test values for granular material. This is due primarily to the higher laboratory strength of the specimen confined in a rigid cylinder. A laboratory procedure is outlined by which specimens are subjected to controlled lateral pressure. A formula is proposed for determining design values from the modified laboratory data on the basis of theoretical bearing capacity considerations through the theory of plasticity. Test results are reported and the verification of the suggested method for determining the design CBR value of granular material is shown.
Geotechnical Properties of Hackensack Valley Varved Clays of New Jersey
Authors: Saxena SK , Hedberg J , Ladd CC 
Published: December 2008

Abstract
A special testing program was conduted on 127-mm (5-in.) diameter samples of varved clay from Hackensack Meadows, the site of a glacial lake near Secaucus, New Jersey. The program included constant rate-of-strain consolidation tests, measurement of K0 versus OCR, permeability tests on cubic samples to determine kh/kv, undrained-unconsolidated triaxial compression tests run on specimens cut at various inclinations, K0 consolidated-undrained direct simple shear tests to establish su (σvc)1/2 versus OCR, and K0 consolidated-undrained triaxial compression and extension tests on normally consolidated samples.
This paper presents the results of the tests and compares the data to that obtained on other varved clays. The basic properties of the Hackensack Valley varved clay are very similar to those for Connecticut Valley varved clays from Amherst and Northhampton, Massachusetts. Two major problems are still unresolved: the in-situ value of kh/kv versus that measured in the laboratory, and the value of undrained strength for horizontal loading, su(h).
Equivalence of Air and Water Permeability Tests in Evaluating Engineering Fabrics
Authors: Carroll RG 
Published: December 2008

Abstract
Permeability characteristics of civil engineering filter fabrics are currently evaluated by three types of tests: air permeability and falling-head and constant-head water permeability. Test procedures for the falling-head and constant-head water permeability tests are discussed, and results from these tests are correlated to air permeability results for filter fabrics. Several commercially available filter media were tested by these methods and a high degree of linearity between the tests was observed.
Investigation of a Plate Index Test for Railroad Ballast
Authors: Panuccio CM , Wayne RC , Selig ET 
Published: December 2008

Abstract
A need exists to determine the physical state of ballast in railroad track. The use of a small surface bearing plate was investigated for this purpose. The measurement problem is particularly difficult because ballast is a coarse, angular material with particle sizes up to 50 to 75 mm (2 to 3 in.) in diameter, for which the bulk properties to be assessed vary over distances as short as 300 mm (1 ft). Thus, the plate size can neither be very small or very large. Laboratory tests were first conducted to determine the effects of the following variables: ballast type, ballast density, ballast layer thickness, plate seating method, plate size, plate shape, and repeated load cycles. The procedures developed were also successfully field-tested. The study showed that using a 127-mm (5-in.) diameter plate with plaster of Paris as a seating material gave the most consistent results. The derived index parameters were found to be significantly affected by all of the variables considered.
Apparatus and Procedures for a Railroad Ballast Plate Index Test
Authors: Panuccio CM , Dorwart B , Selig ET 
Published: December 2008

Abstract
A small field plate bearing test was developed in response to a need for a method for measuring the physical state of railroad ballast. The recommended apparatus and procedures for this test are described in this paper. They evolved from a laboratory investigation of the variables influencing the test and field experience at a variety of track sites.
Accuracy of the Density Scoop for Unit Weight Determinations in Cohesionless Soils
Authors: Weiler WA , Kulhawy FH 
Published: December 2008

Abstract
An assessment is made of the accuracy of the Selig density scoop for determining the unit weight of dry cohesionless soils. Seven different soils were used in the study. The results show grain size and density dependence. Recommendations are made for appropriate field use.
Vacuum Filtration Versus Centrifugation for Sodium Adsorption Ratio Determinations
Authors: Craft D 
Published: December 2008

Abstract
Vacuum filtration and centrifugation, two methods used to separate saturation water from paste for sodium adsorption ratio analyses, are compared for equivalence of results, precision, and analytical time involved. While both methods gave similar results and precision, it was observed that centrifugation was faster.
Determination of Attenuation and Penetration Depth of Microwaves in Soil
Authors: Lord AE , Koerner RM , Reif JS 
Published: December 2008

Abstract
When probing soil with microwaves to locate water, seepage paths, buried metal objects, or other subsurface features, knowledge of two fundamental properties is required. The first, relative dielectric constant, was the subject of an earlier paper. The second, attenuation coefficient, which is used in determining microwave penetration depth, is the subject of this paper. The laboratory testing method in the L band frequency range (∼ 1 GHz) used in this paper is based on open wire transmission line theory and is called OWL II. Using this method on a remolded beach sand, a clayey silt, and a Kaolinite clay at varying water contents (up to 20%) and densities it was found that the measurement technique is straightforward, convenient, rapid, and appears well suited to the evaluation of remolded soils in the laboratory; that attenuation for the three soils was in the range of 1 to 12 nepers/m; that attenuation increases with increasing volumetric water content; that attenuation is slightly lower in the clay soil than in the sand or silt; and that the effective penetration depths calculated with a simple model with these dielectric constant and attenuation data are in good keeping with those determined empirically in the field.
Problems Associated with Permeability Tests of Shells
Authors: SeGall RA , Arman A 
Published: December 2008

Abstract
A preliminary investigation into the use of clam shells as a filter material indicates that it may be inappropriate to use the falling-head permeability test to determine the permeability of this material. Where filters were used a reduction of permeability was observed as a result of clogging. Permeability increased when filters were removed from the test setup, even though there was a gradual increase of the finer particles of shell at the discharge end of the specimen. This behavior suggests the importance of proper modeling of actual field conditions where clam shells are incorporated in the design of a structure.
Sampling and In-Situ Density of a Saturated Gravel Deposit
Authors: Vallee RP , Skryness RS 
Published: December 2008

Abstract
Attempts to sample a saturated gravel deposit beneath a proposed nuclear power plant with standard drilling methods and sampling techniques were unsuccessful. To provide the necessary information on in-situ stratigraphy and density, an alternate exploratory method and sampling technique was designed. In this method, a 107-cm (42-in.) uncased shaft was drilled to a depth of 14.3 m (47 ft) after freezing the soil around the shaft location. The soil stratigraphy, composition, and structure in the uncased shaft were then exposed in great detail for mapping and photographing. Two frozen undisturbed samples were cut from the walls of the shaft in loose gravel layer and the in-situ density was determined using a fluid displacement technique. Maximum and minimum densities were obtained for the thawed soil for calculation of in-situ relative density. Standard Penetration Test (ASTM D 1586, Penetration Test and Split-Barrel Sampling of Soils) results successfully indicated the approximate location and thickness of the loose layer despite the sampling difficulties and high gravel content. Judging from inch-by-inch blow count data, the high gravel content increased the penetration resistance values (through the spoon pushing a large gravel piece) in only a small number of samples.
Suggested Method for the Calibration of Vibrating Tables for Maximum Index Density Testing
Authors: Kaufman LP , Strickland EA , Benavidez AA 
Published: December 2008

Abstract
The amplitude of vibration of the vibrating table used in the ASTM Test for Relative Density of Cohesionless Soils (D 2049-69) has a significant effect on the value of the maximum index dry density obtained for a particular soil specimen. The table vibration must be calibrated to help ensure conformance with a standard test method. A method for this calibration is given and the required apparatus is described. The results of a sample calibration of an electromagnetic vibrating table are shown both for the maximum amplitude setting of the vibrator power control and for various percentages of maximum power. For a linear decrease in amplitude power control setting, there is a nonlinear decrease in the vibration amplitude of the table. Also shown is a method by which the vibrating table can be checked for the presence of rocking motion in the vibration.
Suggested Test Method for Determination of Degree of Saturation of Soil Samples by B Value Measurement
Authors: Chaney RC , Stevens E , Sheth N 
Published: December 2008

Abstract
Three methods are proposed for using Skempton's B parameter for determining levels of soil saturation. In the first method, achievement of a specified B value is required before consolidation of the test specimen. In the second, achievement of a specified B value is required after consolidation of the test specimen. In the third method, the B value remains constant when plotted against increasing back pressure. The detrimental effect of performing a B value test on a partially saturated specimen is discussed, along with methods for increasing specimen saturation by flushing with carbon dioxide gas and increasing back pressure. Data are also presented on recommended B criteria as a function of soil type and saturation level, along with typical times required to flush samples.
Determination of Permeability Anisotropy in a Two-Way Permeameter
Authors: Moore PJ 
Published: December 2008

Abstract
This paper describes the use of a new item of laboratory equipment, a two-way permeameter for determination of the degree of permeability anisotropy of compacted or undisturbed samples of soil. The test is performed on a single sample of soil. The relevant theoretical solutions for seepage flow through the permeameter have been provided, based on exact solutions and manual sketching of flow nets.
A New Direct Simple Shear Device
Authors: Franke E , Kiekbusch M , Schuppener B 
Published: December 2008

Abstract
Existing types of direct simple shear devices are discussed and a newly developed apparatus is presented. This apparatus uses a round specimen that is laterally covered by a rubber membrane and placed in a pressure cell in which vertical and horizontal normal stresses are applied as with triaxial test equipment. The shear stresses are transmitted to the specimen by a horizontally loaded top cap. Zero lateral strain during undrained shearing is achieved through an automatic measuring and regulating system. Procedures and results are described for an undrained cyclic simple shear test on sand and an undrained static strain-controlled test on an undisturbed normally consolidated clay.
Comparisons of Field Density Test Results
Authors: Kaderabek TJ , Ferris WR 
Published: December 2008

Abstract
During the course of a large earthwork project in Georgia, six test fills were constructed to study placement and compaction procedures. Several density testing techniques used in the quality control testing program were compared. A laboratory compaction test was performed at each field density test location to eliminate the need to select the appropriate compaction curve from a family of curves. More than 180 nuclear density, sand cone, and laboratory compaction tests were compared. Two soil types, both sands, were involved in the test program. The effects of gradation, compaction, mold size, depth of density test, and type of nuclear device were investigated. Variables in construction procedures included type of equipment, number of passes, lift thickness, and soil type. Following a statistical evaluation it was concluded that (1) oven moisture contents were consistently lower than nuclear moistures, (2) nuclear wet densities were always less than sand cone densities, and (3) the sand cone density test method yielded a 5% higher compaction when compared to the nuclear test method.
Small-Scale Testing of Soils for Frost Action
Authors: Sayward JM 
Published: December 2008

Abstract
A method is described for convenient study of frost action, including soil heaving and needle ice formation. The apparatus is simple and small and the procedure requires only 25-cm3 soil specimens. The method could be useful for screening either large numbers or limited quantities of soils or soil additives for frost susceptibility.
The method described was used to perform a limited number of tests with several soils. The tests obtained action in the form of soil heave, ice heave, or ice needles, yielding maximum heights up to three to six times the initial 40-mm soil depth. Maximum growth rates were up to 1 to 3 mm/h for soil heaves and 3 to 7 or more mm/h for ice heaves and ice needles. Initial trials showed that thickener additives and possibly other treatments can restrict frost action.
Testing for Evaluation of Stress-Strain Behavior of Clays
Authors: Yudhbir  , Jain KK 
Published: December 2008

Abstract
A technique to predict the stress-strain behavior of clays along various stress paths is presented. The experimental results of stress-controlled triaxial pure shear and consolidation tests conducted on normally consolidated and lightly overconsolidated samples are given, and a method to evaluate the parameters required for prediction by the proposed technique is discussed. Comparison between experimental and predicted stress-strain behavior of normally consolidated and lightly overconsolidated samples along stress paths shows that the technique predicts the behavior quite well.
A Device for Automatic Logging of Volume Change in Large Scale Triaxial Tests
Authors: Watts KS 
Published: December 2008

Abstract
Large-scale (230-mm-diameter) triaxial compression tests are carried out as part of the research work of the Geotechnics Division of the Building Research Station, United Kingdom. It was considered desirable to monitor the tests by using automatic data logging facilities. A new device was designed and built to monitor sample volume change. The gage has been used in a series of tests on rock-fill samples. The device is described and its accuracy and performance are discussed.
Use of the Osmotic Tensiometer to Measure Negative Pore Water Pressure
Authors: Bocking KA , Fredlund DG 
Published: December 2008

Abstract
The osmotic tensiometer was developed to provide a method of direct measurement of tension in the pore water of soils. A study was undertaken at the University of Saskatchewan to investigate the instrument's operational characteristics and its applicability to practical engineering problems. The study covered long-term stability, response time to changes in pore water pressure, and response to changes in ambient temperature. It was found that the internal prestress pressure tended to diminish with time, probably due to leakage of the confined solute through the semipermeable membrane. However, it was possible to individually calibrate each instrument to correct for this effect. Second, the pressure response of the osmotic tensiometers indicated that a transient flow process was occurring; the equilibration time of the device was primarily a function of the configuration and materials of the unit and the compressibility of the solution in the chamber. Third, it was found that changes in ambient temperature considerably affected the internal reference pressures. These results indicate that osmotic tensiometers may be useful to measure negative pore water pressures, providing that the temperature is controlled and the pore water pressure is constant. This may restrict their usefulness to research applications.
A Stress-Controlled Study of Swelling Characteristics of Compacted Expansive Clays
Authors: Dakshanamurthy V 
Published: December 2008

Abstract
The swelling characteristics of statically compacted expansive clays subjected to given isotropic and anisotropic stress conditions were investigated with a triaxial cell apparatus. A unique relationship was found between maximum volumetric swelling and mean normal stresses. From this relationship one can determine a null swelling pressure that will cause neither swelling nor compression or consolidation or both. It was also determined that the maximum axial and radial swelling decrease exponentially with increase in mean normal stress; this relationship is dependent on the principal stress ratio. The swelling ratio (defined as the ratio of axial swelling to radial swelling) was found to decrease with time allowed for swelling, reaching an equilibrium value termed the equilibrium swelling ratio, which is a function of the boundary loading conditions.
Effects of Anisotropic Versus Isotropic Consolidation in Consolidated-Undrained Triaxial Compression Tests of Cohesive Soils
Authors: Donaghe RT , Townsend FC 
Published: December 2008

Abstract
This investigation examines effects of anisotropic versus isotropic consolidation in consolidated-undrained triaxial compression tests performed on specimens of two clays consolidated from a slurry in large-diameter consolidometers. Shear strength and corresponding deformation characteristics were developed in both normally consolidated and overconsolidated ranges. Test results indicate that volume changes during consolidation are not a unique function of the major principal consolidation stress but instead are related to the mean effective consolidation stress and the deviator stress during consolidation. Consequently, for a given major principal consolidation stress, the undrained strength of anisotropically consolidated specimens is lower than that of isotropically consolidated specimens.
Effect of Stress Concentrations on the Cyclic Behavior of Sands
Authors: Chaney RC , Stevens E , Sheth N , Hencey E 
Published: December 2008

Abstract
A laboratory study is presented on the effect of rigid inclusions on the observed cyclic strength of sand specimens. The test program consisted of 20 cyclic triaxial strength tests. Sixteen of these tests were conducted on specimens that had a spherical cemented sand inclusion of varying diameter located in either the middle or upper third of the specimen. The remaining four specimens were homogeneous. Results indicated that the cyclic strength of a specimen with an inclusion was increased up to a maximum of 6 to 7% over that of a corresponding homogeneous specimen at an area ratio (area of inclusion/area of specimen) of 10%. An increase in the area ratio to 25% showed a decrease in cyclic strength to a level similar to that exhibited by a homogeneous specimen. In addition, for a constant area ratio the increase in cyclic strength was shown to be greatest for a low stress ratio.
The Uniaxial Strength of Rock Material
Authors: Wijk G 
Published: December 2008

Abstract
Uniaxial tensile and compressive strength were determined for a granite, a marble, and a sandstone. There was no statistically detectable difference between the strength values of large and small samples, although the volume ratio of the samples was 20 or more. Further, strain gage measurements taken during the compression tests on the granite revealed strength values that were remarkably independent of the unavoidable eccentricities of the sample loads.
Proposed New Method for the Determination of Density of Soil in Place
Authors: Cernica JN 
Published: December 2008

Abstract
A new method is proposed for determining the volume of soil samples extracted for field density tests. The method consists of replacing the extracted soil with sand poured from a graduated cylinder and determining the volume of sand required to fill the hole. In a series of trials, the proposed new method was compared to the Test for Density of Soil in Place by the Sand-Cone Method (ASTM D 1556) and the Test for Density of Soil in Place by the Rubber-Balloon Method (ASTM D 2167). Results indicated that the proposed new method yields lower percentage errors and is less sensitive to edge and surface irregularieties in the sample holes. The new method is also simpler and faster to perform than the sand cone method.
What Constitutes a Turn?
Authors: Kovacs WD 
Published: December 2008

Abstract
There are wide variations in physical configuration and cathead equipment among the available drill rigs used to perform the standard penetration test. Such differences may be partly responsible for variations in blow count among different drill rigs. The paper draws attention to the fact that about half of the available drill rigs use clockwise rotation of the cathead while the others use counterclockwise rotation. Depending on which direction is used, differences in the actual number of turns could be off by as much as half a turn. This difference could result in a substantial variation in the energy delivered to the sampler and in the blow count for the same soil conditions.