Download or read book Undrained Stress Strain Behavior of Unsaturated Sands written by Rolland G. Boehm and published by . This book was released on 1988 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: This final report provides the details of an investigation on the undrained stress strain behavior of partly saturated sands under controlled laboratory conditions. A new triaxial test setup was developed during the previous years of this research study. Thus, the two purposes of the investigation reported in this report were a) to evaluate the usefulness of the new soil test procedure, and b) to determine the behavior of the unsaturated sand samples. An axis translation technique was used to monitor pore water pressure changes during the tests and this appeared to work well. A special ceramic porous stone was used to be able to measure pore water and air pressures separately. The conclusions drawn from this research are that the stress-strain behavior changes little with respect to saturation level until the level approaches about 95%. The initial tangent modulus decreased with an increase in saturation. For lower saturated samples, there seems to be no difference between an undrained and a drained test. The dilation potential of the sand increased with strain rate. The strain rate had some effect on the initial modulus of only the dense samples of sand.

Download or read book Uniaxial Stress Strain Behavior of Unsaturated Soils at High Strain Rates written by and published by . This book was released on 1994 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Split-Hopkinson Pressure Bar was used to study the uniaxial stress-strain behavior of compacted moist soils under one-dimensional, undrained, confined compression loading at high strain rates (1000/sec and 2000/ sec. Three soils, Eglin Sand, Tyndall sand and Ottawa 20-20 sand were tested. The results suggest that the stress strain response is dominated by the water- phase from the lock-up strain and beyond. The soil skeleton dominates the response from the start of loading up to the lock-up strain. It appears that there may be some strain-rate effects, however, the data arc insufficient to adequately demonstrate this and further investigation is suggested. The research described in this report has demonstrated that the Split-Hopkinson Bar System is a viable technique for high strain rate dynamic geotechnical testing of unsaturated, saturated, and dry soils, and provides a framework for conducting further studies. Split-Hopkinson pressure bar, Tyndall sand, Ottawa 20-20 sand, Uniaxial stress strain.

Download or read book Cyclic Undrained Stress strain Behavior of Dense Sands by Torsional Simple Shear Test written by Fumio Tatsuoka and published by . This book was released on 1981 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Method of Sample Preparation on the Stress strain Behavior of Sands in Undrained Stress controlled Triaxial Tests written by Michael G. Donnelly and published by . This book was released on 1980 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Dynamic Undrained Uniaxial Stress strian Behavior of Unsaturated Sands written by Michael Carnivale and published by . This book was released on 2001 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unsaturated Soil Behavior Under Monotonic and Cyclic Stress States written by Byoung-Jae Mun and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this dissertation are to measure and calculate surface free energies of soil particles, to understand the mechanical behavior of unsaturated silty sand through first studying the stress-strain relationship, the effects of matric suction and pore water chemistry and second to interpret the behavior by the critical state frame work, to develop a method to predict cone tip resistance in unsaturated soils, and to present the concept of pseudo strain and dissipated pseudo strain energy. Universal Sorption Device (USD) is developed to measure surface free energies of soil particles. The test results on a soil sample shows that specific surface area increased with decreasing particle size. The components of surface free energies and the work of adhesion increased with decreasing particle size. A servo controlled triaxial testing device is developed to test 15.24 cm in height and 7.62 cm in diameter, recompacted specimens of unsaturated soil under varying matric suction and different pore chemistry. During the test, the matric suction is maintained constant. Results from the triaxial drained tests are used for validation of the constitutive models proposed by Alonso et al. (1990). Predictions from the model are in good agreement with experimental results. The critical state model for unsaturated soil is used to calculate cone tip resistance in unsaturated silty sand. The calculated cone tip resistance is used to evaluate the liquefaction potential of unsaturated soils. The results from the stress based liquefaction potential analysis reveal that even in an unsaturated condition soil is susceptible to liquefaction. By applying the pseudo strain concept, it is possible to account for the viscous resistance of water during cyclic loading. The results of undrained cyclic triaxial tests are used to calculate pseudo-strain and dissipated pseudo strain energy. The results of calculated dissipated pseudo strain energy suggest that the effect of initial matric suction is evident. On the other hand, the effect of surface tension increase or decrease due to existence of chemical on the pore water is negligible.

Download or read book Unsaturated Soil Mechanics from Theory to Practice written by Zhenghan Chen and published by CRC Press. This book was released on 2015-10-14 with total page 924 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past decades advances have been made in the research and practice on unsaturated soil mechanics. In 2000 the first Asia-Pacific Conferences on Unsaturated Soils was organized in Singapore. Since then, four conferences have been held under the continued support of the Technical Committee on Unsaturated Soils (TC106) of the International Socie

Download or read book Moisture Effects on the Undrained Dynamic Behavior of Calcareous Sand at High Strain Rates written by Yaru Lv and published by . This book was released on 2019 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dynamic behavior of calcareous sand at high strain rates (HSRs), which is relevant to mining industry, aircraft wheel loading, and pile driving, is still not fully understood. To investigate the effects of the moisture content, 34 HSR tests and 26 low strain rate (LSR) tests were conducted on calcareous and silica sands using the split Hopkinson pressure bar (SHPB) technique with a rate ranging between 100s-1and 104s-1and using a mechanical testing and simulation (MTS) apparatus with a rate ranging between 10-5s-1and 10-1s-1, respectively. It is found that the compression of unsaturated sand is almost larger than that of dry sand because the compressibility of particles and effective confining pressure change with moisture content. The dynamic stress-strain curve of unsaturated silica sand moves upward with moisture content at HSRs, but that of unsaturated calcareous sand is insensitive to moisture content. Compared with silica sand, calcareous sand reached its optimum capacity for energy absorption at lower stresses and energies. The energy absorption of unsaturated sand decreases with an increasing moisture content, while its transmitted load increases. To improve the cushioning properties of sand, a moderate water content is proposed.

Download or read book Bifurcation and Degradation of Geomaterials with Engineering Applications written by Euripides Papamichos and published by Springer. This book was released on 2017-04-21 with total page 589 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the scientific contributions to the 11th International Workshop on Bifurcation and Degradation in Geomaterials (IWBDG) held in Limassol-Cyprus, May 21-25, 2017. The IWBDG series have grown in size and scope, since their inception 30 years ago in Germany, covering more and wider areas of geomaterials and geomechanics research including modern trends. The papers cover a wide range of topics including advances in instabilities, localized and diffuse failure, micromechanical, multiscale phenomena, multiphysics modeling and other related topics. This volume gathers a series of manuscript by brilliant international scholars who work on modern recent advances in experimental, theoretical and numerical methods. The theoretical and applied mechanics are linked successfully with engineering applications in traditional and in emerging fields, such as geomechanics for the energy and the environment. The quality of the contributed papers has benefited from the peer review process by expert referees. This book can be used as a useful reference for research students, academics and practicing engineers who are interested in the instability and degradation problems in geomaterials, geomechanics, geotechnical engineering and other related applications.

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1970 with total page 772 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unsaturated Soils Advances in Geo Engineering written by D.G. Toll and published by CRC Press. This book was released on 2008-06-23 with total page 1008 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unsaturated Soils: Advances in Geo-Engineering comprises 136 contributions from leading international researchers and practitioners, presented at the First European Conference on Unsaturated Soils (Durham, UK, 2-4 July 2008). The papers report on the latest advances in geo-engineering aspects of unsaturated soils. It is the first collection to focu

Download or read book Undrained Behavior of Sandy Soils Subjected to Simultaneous Cyclic and Monotonic Straining written by Sh-Quan Lin and published by . This book was released on 1998 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unsaturated Soils written by E. J. Murray and published by John Wiley & Sons. This book was released on 2010-06-17 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: An understanding of the mechanical properties of unsaturated soilsis crucial for geotechnical engineers worldwide, as well as tothose concerned with the interaction of structures with the ground.This book deals principally with fine-grained clays and silts, orsoils containing coarser sand and gravel particles but with asignificant percentage of fines. The study of unsaturated soil is a practical subject, linkingfundamental science to nature. Soils in general are inherentlyvariable and their behaviour is not easy to analyse or predict, andunsaturated soils raise the complexity to a higher level. Evenamongst practicing engineers, there is often lack of awareness ofthe intricacies of the subject. This book offers a perspective ofunsaturated soils based on recent research and demonstrates howthis dovetails with the general discipline of soil mechanics. Following an introduction to the basic soil variables, thephases, the phase interactions and the relevance of soil structure,an up-to-date review of laboratory testing techniques is presented.This includes suction measurement and control techniques intriaxial cell testing. This is followed by an introduction tostress state variables, critical state and theoretical models inunsaturated soils. A detailed description of the thermodynamic principles asapplied to multi-phase materials under equilibrium conditionsfollows. These principles are then used to explore and develop afundamental theoretical basis for analysing unsaturated soils. Soilstructure is broken down into its component parts to developequations describing the dual stress regime. The critical statestrength and compression characteristics of unsaturated soils areexamined and it is shown how the behaviour may be viewed as athree-dimensional model in dimensionless stress-volume space. Theanalysis is then extended to the work input into unsaturated soilsand the development of conjugate stress, volumetric andstrain-increment variables. These are used to examine themicromechanical behaviour of kaolin specimens subjected to triaxialshear strength tests and lead to observations not detectable byother means. Unsaturated Soils: A fundamental interpretation of soilbehaviour covers a rapidly advancing area of study, researchand engineering practice and offers a deeper appreciation of thekey characteristics of unsaturated soil. It provides students andresearchers with a framework for understanding soil behaviour anddemonstrates how to interpret experimental strength and compressiondata. provides engineers with a deeper appreciation of keycharacteristics of unsaturated soils covers a rapidly advancing area of study, research andengineering practice provides students and researchers a framework for understandingsoil behaviour shows how to interpret experimental data on strength andcompression the limited number of books on the subject are all out ofdate

Download or read book Unsaturated Soils Research Applications written by Adrian R. Russell and published by CRC Press. This book was released on 2020-09-24 with total page 1321 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the contributions to the Second European Conference on Unsaturated Soils, E-UNSAT 2012, held in Napoli, Italy, in June 2012, and includes more than one hundred papers, addressing three thematic areas: experimental, modelling, and engineering.

Download or read book Technical Reports Awareness Circular TRAC written by and published by . This book was released on 1988-06 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Deformation Behavior of Fine Sand written by Han-Wei Yang and published by . This book was released on 1987 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Specimen Preparation Method on the Stress Strain Behavior of Sand in Plane Strain Compression Tests written by D. Wanatowski and published by . This book was released on 2008 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental results are presented in this paper to study the effect of specimen preparation method on the stress-strain behavior of sand in plane-strain compression tests. The data obtained from K0 consolidation, drained, undrained and strain path tests conducted on medium loose specimens prepared by the moist-tamping (MT) and the water sedimentation (WS) methods are compared. The test data show that the plane-strain compression behavior of medium loose sand under K0, drained and strain-path controlled (including undrained) conditions is affected by the specimen preparation method. Under K0 conditions, the K0 values obtained from the MT specimens are generally lower than those obtained from the WS specimens. Under drained conditions, more contractive behavior was observed for the MT sand. However, the failure stress ratio (or the failure friction angle) was not affected by the specimen preparation method. The data presented in this paper also illustrate that the compression behavior of medium loose sand in strain-path testing can be affected by the specimen preparation method. However, the differences in the stress-strain behavior will also depend on the strain increment ratio (d?v/d?1) imposed on the specimens. In general, different behaviors of the moist-tamped and water-deposited specimens reflect the influence of soil fabrics on the stress-strain behavior of sand.