Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

PDF

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type

Articles 158191 - 158220 of 187304

Full-Text Articles in Engineering

Spouses Program, Multiple Participants Mar 2001

Spouses Program, Multiple Participants

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

Go to article

Keynote Lecture: Recent Studies On Liquefaction Resistance Of Sand-Effect Of Saturation, K. Ishihara, H. Tsuchiya, Y. Huang, K. Kamada Mar 2001

Keynote Lecture: Recent Studies On Liquefaction Resistance Of Sand-Effect Of Saturation, K. Ishihara, H. Tsuchiya, Y. Huang, K. Kamada

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The problem of sandy soils as to how they behave when they contain air or gas has been recently addressed in relation to evaluation of cyclic resistance during earthquakes. In order to shed some light on this issue, some laboratory tests were conducted on sand samples prepared in the triaxial test apparatus. The outcome of the tests disclosed that the degree of imperfect saturation can be quantified by way of the propagation velocity Vp of compressional wave or P-wave and that the cyclic resistance exhibits significant increase if the velocity Vp drops below 700 m/sec, a value smaller than the …

Go to article

Table Of Contents, Multiple Authors Mar 2001

Table Of Contents, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

Go to article

Soil Viscous Behavior In Response To Torsional Cyclic Loading, Jiang Li Mar 2001

Soil Viscous Behavior In Response To Torsional Cyclic Loading, Jiang Li

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

In the present paper, experimental investigations of dynamic behavior of soils under periodic loading are conducted. Investigations include two aspects. First, effect of confining pressure and loading frequency on soil dynamic behavior and stress-strain relation is studied. Second, effect of confining pressure, loading frequency and amplitude of cyclic shear stress on soil viscosity is investigated. In the first aspect, based on test curves, physical nonlinearity shown in soil stress-strain relation suggests that physical parameters of soil materials are not constant. For example, soil elastic parameters can be a function of cyclic shear strain, confining pressure and loading frequency. In the …

Go to article

Effect Of Anisotropy On Drained And Undrained Shear Behavior Of In-Situ Sandy Soils, Akihiko Uchida, Munenori Hatanaka, Yuji Taya Mar 2001

Effect Of Anisotropy On Drained And Undrained Shear Behavior Of In-Situ Sandy Soils, Akihiko Uchida, Munenori Hatanaka, Yuji Taya

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Two different types of undisturbed cylindrical specimen (V-specimen: the axis is parallel to the direction of sedimentation, and H-specimen: the axis is perpendicular to the direction of sedimentation), were prepared from high quality undisturbed sand column obtained by in-situ freezing technique. A series of drained compression and extension tests (CD, test, CD, test) and cyclic undrained triaxial tests (liquefaction test) on these samples were performed in order to investigate the effect of the anisotropy on the drained and undrained shear behavior. Following were concluded. 1) The effect of anisotropy on both internal friction angle and liquefaction strength is negligible. 2) …

Go to article

Cyclic Torsional Shear Tests On Liquefaction Resistance Of Sands Under Low Confining Stress, Jinichi Koseki, Daisuke Itakura, Sadahiro Kawakami, Takeshi Sato Mar 2001

Cyclic Torsional Shear Tests On Liquefaction Resistance Of Sands Under Low Confining Stress, Jinichi Koseki, Daisuke Itakura, Sadahiro Kawakami, Takeshi Sato

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A series of undrained cyclic torsional shear tests was conducted to investigate the effects of initial confining stress level on liquefaction resistance of sand. Hollow-cylindrical dense specimens with outer diameter of 10 cm, inner diameter of 6 cm and height of 20 cm are prepared with two kinds of sand. After being saturated, they were isotropically consolidated under an initial confining stress σc’ of 4.9, 9.8 or 98 kPa, and subjected to undrained cyclic torsional shear while maintaining the axial and lateral stresses constant. The amplitude of the cyclic torsional shear stress τcy was kept constant with …

Go to article

Seismic Response Calculation Of Saturated Soft Soil, Huang Yu, Ye Weimin, Tang Yiqun, Chen Zhuchang Mar 2001

Seismic Response Calculation Of Saturated Soft Soil, Huang Yu, Ye Weimin, Tang Yiqun, Chen Zhuchang

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

In this paper, Shanghai saturated soft soil is modeled as a two-phase porous media system consisting of solid and fluid phases. On the basis of resonant column test and dynamic triaxial test data of Shanghai saturated soft soil, the dynamic calculation model including a set of relationships of stress, strain, and pore water pressure and earthquake subsidence is developed to compute the seismic response of soil. The procedure to identify soil constants for the dynamic calculation model is also reported in detail. Subsequently, a dynamic effective stress analysis with the finite element method has been recommended to predict the seismic …

Go to article

Effects Of Soil Fabric On Undrained Behavior Of Sands, S. Yimsiri, K. Soga Mar 2001

Effects Of Soil Fabric On Undrained Behavior Of Sands, S. Yimsiri, K. Soga

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The undrained behavior of sands in monotonic triaxial compression and extension tests was simulated using the Distinct Element Method (DEM). Soil specimens were prepared at different initial soil fabrics but at similar void ratios and the effects of soil fabric on the undrained behavior were investigated. The DEM results show that soil fabric and its change have profound effects on the undrained response of sands. They also provide some insights for the interpretation of the published experimental data that show the effects of specimen reconstitution methods and of preshearing on the undrained behavior of sands.

Go to article

Site Response Of Organic Soils, Rajendram Arulnathan, R. W. Boulanger, I. M. Idriss Mar 2001

Site Response Of Organic Soils, Rajendram Arulnathan, R. W. Boulanger, I. M. Idriss

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A primary source of uncertainty in any evaluation of the seismic stability of the Sacramento-San Joaquin Delta levee system is the site response characteristics of the shallow organic soils that commonly underlay the levees. This paper provides an overview of recent research on the site response characteristics of organic soils using centrifuge and numerical modeling. The centrifuge modeling effort included the development of techniques to measure the shear wave velocity profile for a centrifuge model while in-flight. One-dimensional site response analyses using an equivalent linear procedure were performed with the measured shear wave velocity profiles and the modulus reduction and …

Go to article

Global Methodology For Soil Behavior Identification And Its Application To The Study Of Site Effects, A. Modaressi, F. López-Caballero Mar 2001

Global Methodology For Soil Behavior Identification And Its Application To The Study Of Site Effects, A. Modaressi, F. López-Caballero

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Though it is now admitted that non-linear modeling of soil behavior is necessary to represent some important aspects of the soil response under strong ground motion (for example, irreversible settlements and pore-pressure build-up), the elastoplastic models are not yet used in the everyday design processes. One of the obstacles is the difficulty to identify the models’ parameters. A methodology to identify the soil mechanical parameters is presented and applied to an elastoplastic model. The strategy is based on the use of minimum physical and easily measurable parameters. The key parameter necessary for characterizing the clay is its Liquidity Limit, while …

Go to article

Dynamic Loading-Deformation Performance Of Peat Soil Under Large Concrete Plates, Mark Vakher Mar 2001

Dynamic Loading-Deformation Performance Of Peat Soil Under Large Concrete Plates, Mark Vakher

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

This paper presents data from a series of investigations performed with peat soil to determine resilient deformation under dynamic load, which has great influence on the design of connections between concrete plates that are used as pavement for rural roads. The experiments were performed both in situ and under laboratory conditions using a concrete plate, size 3m by 1 m by 0.15m placed over peat. Other experiments were made with the concrete plate placed over the various thicknesses of sand fill above the surface of peat soil. Experiments were carried out under dynamic load. The laboratory experiments were conducted with …

Go to article

Dynamic Response Of Mud In The Field Soil Improvement With Dynamic Drainage Consolidation, Zhangming Li, Mengdong Li, Qiang Feng Mar 2001

Dynamic Response Of Mud In The Field Soil Improvement With Dynamic Drainage Consolidation, Zhangming Li, Mengdong Li, Qiang Feng

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The dynamic drainage consolidation (DDC) method is a relatively new technology for soft soil improvement. The method was adopted for the improvement of the mud at a site for the construction of a highway. The in-situ monitoring on the porewater pressures and settlements of the mud were taken for understanding its field dynamic properties. The site original data on the mechanical responses of the mud under dynamic loading were obtained and analyzed. The some important phenomena on pore water pressures were observed. The settlements induced by dynamic tamping and soil fill were also observed. Some basic mechanisms on the behavior …

Go to article

Static And Dynamic Properties Of Leighton Buzzard Sand From Laboratory Tests, Antonio Cavallaro, Michele Maugeri, Rosalia Mazzarella Mar 2001

Static And Dynamic Properties Of Leighton Buzzard Sand From Laboratory Tests, Antonio Cavallaro, Michele Maugeri, Rosalia Mazzarella

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The Leighton Buzzard sand is an English sand commonly used at the University of Bristol to study soil-shallow foundation interaction (Maugeri et al., 1999a; 199b) and soil-retaining wall interaction (Carafa et al., 1998) by means of the shaking table. These experiments require an accurate definition of geotechnical characterisation of soil. To define the mechanical behaviour of uncemented Leighton Buzzard sand a large number of static and dynamic laboratory tests were performed on dry reconstituted specimens. The static tests includes direct shear tests performed on specimens reconstituted by pluvial deposition method with different relative density Dr. To evaluate the …

Go to article

Application Of Fk Analysis Of Surface Waves For Geotechnical Characterization, Sebastiano Foti, Renato Lancellotta, Laura V. Socco, Luigi Sambuelli Mar 2001

Application Of Fk Analysis Of Surface Waves For Geotechnical Characterization, Sebastiano Foti, Renato Lancellotta, Laura V. Socco, Luigi Sambuelli

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Since the introduction of the SASW method the use of surface waves for soil characterization has gained great popularity in geotechnical engineering. The typical two-receiver testing configuration shows some inherent drawbacks, for this reason a multistation approach is proposed in this paper. The dispersion curve evaluation with a multistation scheme has several advantages. First of all, the estimate is much more stable and less sensitive to noise and internal phases of the instruments. Moreover signal interpretation is much clearer with respect to SASW approach and there is no need for subjective choices in the construction of the experimental dispersion curve. …

Go to article

Automated Analysis Procedure For Interpreting Results From Impulse Shear Tests, Wanda Henke, Robert Henke Mar 2001

Automated Analysis Procedure For Interpreting Results From Impulse Shear Tests, Wanda Henke, Robert Henke

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

In this paper, we present and discuss an automated analysis procedure for interpreting results from torsional cylindrical impulse shear tests. The “impulse shear test” is an in situ geotechnical test that provides detailed information on in situ nonlinear inelastic shearing deformation characteristics needed for dynamic geotechnical earthquake engineering analysis procedures. The test addresses the issue of effects of disturbances to in situ conditions. The automated analysis procedure is intended to be a major improvement over our existing approach for interpreting results from impulse shear tests. We demonstrate the automated analysis procedure by using the procedure to interpret results from impulse …

Go to article

Prediction Of Volumetric Strain For Sand Under Cyclic Loading, Habib Shahnazari, Ikou Towhata Mar 2001

Prediction Of Volumetric Strain For Sand Under Cyclic Loading, Habib Shahnazari, Ikou Towhata

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

In order to investigate volume change of sand due to cyclic loading, different tests were performed on hollow cylindrical specimens under drained cyclic simple shear condition. Correlation of accumulated plastic shear energy with volumetric strain and effects of different parameters such as initial confining pressure, initial anisotropic consolidation and strain amplitude on this correlation were studied. Test results showed that volumetric strain of sand under different initial confining pressures was almost same. Volume change of specimens with different initial anisotropic consolidations was also identical, except for initial stage of shearing. It was found that the correlation of volumetric strain and …

Go to article

Comparison Of Frequency Spectra For Micotremors, After Shocks (M=2.5-4.7) And The Main Shock Of The Spitak Earthquake Obtained On Massive Lake-River Formations In The Region Of Giumry (Armenia), Hrachya Abrahamyan Mar 2001

Comparison Of Frequency Spectra For Micotremors, After Shocks (M=2.5-4.7) And The Main Shock Of The Spitak Earthquake Obtained On Massive Lake-River Formations In The Region Of Giumry (Armenia), Hrachya Abrahamyan

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

On December 7, 1988 a disastrous earthquake with magnitude M=7.0 took place in the northern part of Armenia, during which in Giumry (former Leninakan) large-scale destruction of standardized buildings with epicentral distance 35 km was observed. This forced us to set a task: to find connection between large-scale destruction and some dynamic peculiarities of grounds on the territory of the city. The present article makes an attempt to explain the significance of the upper engineering-geological stratum (20-30 m) and that of the lower massive lake-river formations. Basing ourselves on a great number of instrumental observations we tried to compare prevailing …

Go to article

Influence Of Micro-Structure On Small-Strain Stiffness And Damping Of Fine Grained Soil And Effects On Local Site Response, Anna D'Onofrio, Francesco Silvestri Mar 2001

Influence Of Micro-Structure On Small-Strain Stiffness And Damping Of Fine Grained Soil And Effects On Local Site Response, Anna D'Onofrio, Francesco Silvestri

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Various experimental studies have shown that soil micro-structure strongly influences the small strain stiffness and damping (G0, D0) of fine-grained soils, as well as their variation with shear strain γ. This dependency, in turn, is expected to influence the local site response. This paper firstly synthesizes the dependency of G0 and D0 on stress state through power relationships, expressed in terms of dimensionless parameters, obtained by fitting a large number of experimental data collected on normally consolidated natural clays. Thereafter, these parameters were correlated to soil micro-structure, by assuming the plasticity index Ip …

Go to article

Use Of Cyclic Simple Shear Testing In Evaluation Of The Deformation Potential Of Liquefiable Soils, A. M. Kammerer, J. Wu, M. Riemer, J. M. Pestana, R. B. Seed Mar 2001

Use Of Cyclic Simple Shear Testing In Evaluation Of The Deformation Potential Of Liquefiable Soils, A. M. Kammerer, J. Wu, M. Riemer, J. M. Pestana, R. B. Seed

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

In recent years, a significant research effort has been focused on assessing the performance of structures founded on potentially liquefiable materials. While significant progress has been made on predictive tools for cases in which large deformations are likely, the ability to accurately and reliably predict small to moderate lateral deformations (<1m) has proven more elusive. As a result, there is a universal need for high quality, element-level laboratory test data to calibrate and validate constitutive laws and numerical models for predicting the deformation of soil with limited liquefaction potential. To address this increasingly urgent need, a comprehensive cyclic simple shear testing program on liquefiable sands has been undertaken using the UC Berkeley Bi-directional Simple Shear Device. Many of the tests performed have new and innovative aspects that can provide information and insight into the behavior of soils showing limited deformation potential. Descried in this paper are results from a Kα test series, which replicates sloping ground conditions, and a newly developed and innovative “fabric” test series, which examines the influence of previous loading history on soil fabric and behavior.

Go to article

Suggestion Of Empirical Equations For Damping Ratio Of Plastic And Non-Plastic Soils Based On The Previous Studies, Dugkeun Park, Harry E. Stewart Mar 2001

Suggestion Of Empirical Equations For Damping Ratio Of Plastic And Non-Plastic Soils Based On The Previous Studies, Dugkeun Park, Harry E. Stewart

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Several empirical correlations between damping ratio with various factors are available and many researchers have developed empirical correlations between damping ratio and normalized shear modulus. Regardless of the appearance of the equations, the estimation of the damping ratio from the normalized shear modulus at any given shear strain amplitude is possible. In this paper, thirty-two sets of normalized shear modulus versus damping ratio from ten references are used to find a new empirical equation for damping ratio of sandy soils. For clayey soils, more than forty sets of normalized shear modulus versus damping ratio from nine references are used. After …

Go to article

An Approach To Predict Shear Modulus Of Soils In The Range Of 10-6 To 10-2 Strain Levels, António Gomes Correia, Jaime Santos, José Maria C. Barros, Sussumu Niyama Mar 2001

An Approach To Predict Shear Modulus Of Soils In The Range Of 10-6 To 10-2 Strain Levels, António Gomes Correia, Jaime Santos, José Maria C. Barros, Sussumu Niyama

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

This paper presents the results of several resonant column tests carried out in a large variety of soils, including lateritic and saprolitic tropical soils. The data analysed are restricted to the strain dependence of shear modulus in the range of 10-6 to 10-2. Despite the different isotropic consolidated stresses, degrees of saturation and overconsolidation ratios applied for the different types of soil, all the test results fit very well in a previous proposed normalised curve of G/G0 as a function of γ/γ0.7, where γ0.7 is the shear strain corresponding to a value of …

Go to article

Dynamic Youngis Modulus And Axial Strain Relationships, X. J. Zhang, M. S. Aggour Mar 2001

Dynamic Youngis Modulus And Axial Strain Relationships, X. J. Zhang, M. S. Aggour

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Equations of Young’s moduli of sands as a function of the axial strain amplitude for different types of dynamic loading were developed from a series of resonant column tests. Ottawa 20-30 sand specimens were excited longitudinally with one of three types of loading at three different confining pressures. In the sinusoidal tests, excitation signals were generated by a variable frequency sine-wave oscillator. In the random tests, input signals were generated by a white-noise generator and a pulse signal generator was used in the impulse tests. Input and output signals were analyzed by an FFT analyzer in the random and impulse …

Go to article

Evaluation Of Deformation-Strength Properties Of Volcanic Soils By Laboratory And In-Situ Testings, Tsuyoshi Asonuma, Seiichi Miura, Munetaka Mae Mar 2001

Evaluation Of Deformation-Strength Properties Of Volcanic Soils By Laboratory And In-Situ Testings, Tsuyoshi Asonuma, Seiichi Miura, Munetaka Mae

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The present study aims to clarify the deformation-strength properties of natural grounds consisting mainly of volcanic coarse-grained soils. Site investigations using cone penetration test (CPT), standard penetration test (SPT) and seismic cone penetration test (SCT) were performed at three sites in Hokkaido, Japan. In addition to these in-situ tests, a series of cyclic triaxial test on the undisturbed samples taken from their sites were also carried out to obtain the pseudo elastic shear modulus and damping ratio and their dependencies on strain level. From the test data, it was found that; (1) N-values obtained from SPT on crushable volcanic grounds …

Go to article

The Influence Of Lateral Faults In The Nonlinear Analysis In An Alluvionar Valley, Marcel Vasile Sincraian, Carlos Sousa Oliveira, J. V. Lemos Mar 2001

The Influence Of Lateral Faults In The Nonlinear Analysis In An Alluvionar Valley, Marcel Vasile Sincraian, Carlos Sousa Oliveira, J. V. Lemos

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The nonlinear dynamic behavior of an alluvionar valley situated in São Sebastão region in Terceira island (Azores archipel) is performed. The Mohr-Coulomb model is used in this paper. A bidimensional cross-section with 1240 m long and 250 m depth is considered. The cross-section of the model is composed by layers having different type of ground, each one having their own geotechnical characteristics. The Distinct Element method is employed in this case. UDE Code is used. The size of Finite Elements has been tailored to the wavelength of the propagating waves through the layers. The objectives of this paper are: 1) …

Go to article

Influence Of Compaction And Loading Conditions Of The Dynamic Properties Of A Silty Sand, Jean-Marie Fleureau, Emmanuel Dufour-Laridan, Antônio Gomes Correia Mar 2001

Influence Of Compaction And Loading Conditions Of The Dynamic Properties Of A Silty Sand, Jean-Marie Fleureau, Emmanuel Dufour-Laridan, Antônio Gomes Correia

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Elastic properties of a compacted silty sand were measured in a precision triaxial cell at the École Centrale de Paris in the range of very small strains (between 10-6 and 10-4), using improved Hall effect-based local strain gauges and data acquisition system. The dynamic properties of the soil were also derived from resonant column tests at the IST, in Lisbon, as functions of shear strain, compaction water content and confining pressure. Elastic limits as low as 5.10-6 were found in both devices, with Poisson’s ratio from triaxial tests ranging from 0.05 at very strains (< 10-4 …

Go to article

Improvement Of Static And Dynamic Properties Of Soft Clay Using High Pressure Jet Grout, Chang Tzyy-Shiou, Vedula V. Ramakumar, Chang Kuo-Ping Mar 2001

Improvement Of Static And Dynamic Properties Of Soft Clay Using High Pressure Jet Grout, Chang Tzyy-Shiou, Vedula V. Ramakumar, Chang Kuo-Ping

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A proposed subway project is located in an area marked by a number of soft clay layers situated at depths from 60 ft to 100 ft below the ground surface. With unconfined compressive strength less than 0.6 tsf these natural soils are not strong enough to support on coming heavy loads and vibrations that the subway may be subject to in future. Hence the soil was trial grouted in-situ using high pressure jet grout technique to improve the engineering properties of the natural clay. A series of static and dynamic property tests were carried out on 18 samples selected from …

Go to article

Dynamic Behavior Of Tropical Soils From Medllin, Colombia, Manuel R. Villarraga Mar 2001

Dynamic Behavior Of Tropical Soils From Medllin, Colombia, Manuel R. Villarraga

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Medellin City has a population of about 2,000,000 people and its area is lower than 110 km2. This city is located in the northwest of Colombia, that is in the northwest corner of South America, which is a zone with a complex tectonic environment associated to the interaction of the Naza, Suramerica and Caribe plates. The result of these conditions implies that Medellin has an intermediate seismic hazard. This city was developed on tie valley of Medellin River and his slopes, has a complex geology, which is composed by alluviums, colluviums of different ages, residual soils from igneous …

Go to article

Plasticity Based Liquefaction Criteria, Carmine Polito Mar 2001

Plasticity Based Liquefaction Criteria, Carmine Polito

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Since their introduction into Chinese building codes in the 1970’s, plasticity-based liquefaction criteria have provided a means for evaluating the liquefaction susceptibility of sands with clayey fines. These criteria are used to separate soils that may be considered non-liquefiable from those susceptible to liquefaction. The majority of the proposed criteria contain some minimum requirement regarding clay content and soil plasticity. The results of a parametric study into the effects of plastic fines content and plasticity on the liquefaction susceptibility of sandy soils were used to evaluate the accuracy of several of the more commonly used plasticity-based liquefaction criteria. Most of …

Go to article

Shear Wave Velocity Relations For Silty And Gravely Soils, S. Thevanayagam, J. Liang Mar 2001

Shear Wave Velocity Relations For Silty And Gravely Soils, S. Thevanayagam, J. Liang

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Shear wave velocity vs, dynamic shear modulus Gmax, and damping characteristics are important parameters required for both static and dynamic response analyses of earth structures. Traditional indirect methods for estimation of these parameters based on void ratio, relative density, and mean effective stress have been successful for rather narrowly graded soils, but not for the most commonly found silty and gravelly soils. Their direct application to determine the above characteristics for silty and gravely soils are not satisfactory. A primary reason for this is that global void ratio is not a good measure of intergrain contact …

Go to article

Measurement Of Dynamic Properties Of Clay Using The Downhole Freestanding Shear Device, Michael F. Riemer, Carlton Grizzle, Osama Safaqah Mar 2001

Measurement Of Dynamic Properties Of Clay Using The Downhole Freestanding Shear Device, Michael F. Riemer, Carlton Grizzle, Osama Safaqah

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The Downhole Freestanding Shear Device is a new, in situ tool for measuring the dynamic properties of cohesive soil deposits. It has been designed and developed to perform cyclic torsional shear tests on freestanding specimens beneath the bottom of a cased borehole, with the goal of measuring local strains on soil which has not been significantly disturbed by the drilling, sampling, or unloading/reloading processes associated with conventional laboratory testing. The research team has completed the device, and is now in the process of validating its performance, first in a laboratory setting. The current paper presents results from the initial tests …

Go to article

First Prev Next Last