Download or read book Undrained Behavior of Fully and Nearly Saturated Sand at High Stresses Under Multiaxial Loading Conditions written by Nasser Massoudi and published by . This book was released on 1988 with total page 795 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Undrained Response of Monterey 0 30 Sand Under Multidirectional Cyclic Simple Shear Loading Conditions written by Ann Marie Kammerer and published by . This book was released on 2002 with total page 940 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Mechanical Behavior of Sand Subjected to Impact Loading written by Sudheer Sudhakaran Prabhu and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Sand is generally subjected to quasi-static loading in the field. However, for applications involving projectile impacts and surface or mine blasts, sand is subjected to high strain-rate loading. To predict the response of underground structures under these loading conditions, there is a need to accurately understand the high strain-rate response of sand overlaying these structures. Researchers noted that the split Hopkinson pressure bar (SHPB) tests provide reliable data on the high strain-rate response of sand and have been extensively used. SHPB studies on sand showed that the stress-strain response of sand is dependent on the water content of the specimen and the particle breakage of sand grains. Several numerical models have been developed through the years to capture the high strain-rate sand response accurately. However, these models were developed mainly for dry sands, completely saturated sands, and sand with high water contents. These numerical models are unable to capture the softening and subsequent stiffening stress-strain behavior observed in sands at low water contents and low stresses. In this study, SHPB tests of sands are numerically simulated and the equations of state (EOS) at different water contents are calibrated using back calculation. The back-calculated EOSs are used to calibrate a three-phase model capable of capturing the sand response at varying water contents. The response predicted by the three-phase model is validated by comparing the numerical and experimental stress-strain responses. A parametric study was carried out to understand the effect of interface friction and aspect ratio on the validity of the SHPB results by considering different aspect ratios and interface frictions for the specimens. The results iv showed that specimens with higher aspect ratio take longer time to achieve stress equilibrium while specimens with interface friction never attain perfect stress equilibrium. Another important factor that affects the high strain-rate stress-strain response of sand is the particle breakage of sand grains. Due to the difficulty of continuum-scale models in capturing particle breakage in sands, discrete element method (DEM) is used to model high strain-rate loading of sand specimens. The study tries to understand the effectiveness of particle upscaling-downscaling procedure adopted in DEM in modeling high strain-rate problems. In this study, several SHPB tests reported in literature are modeled in DEM with particle breakage introduced in these simulations. The results showed that with well-calibrated parameters for contact behavior and particle crushing, specimens with upscaled particle size distribution (PSD) provide similar dynamic stress-strain response and PSD evolution as those reported in literature. This study shows the importance of particle breakage in the stress-strain response under high stresses as the specimens without particle breakage yield a much stiffer response compared to the specimens with particle breakage. The developed DEM model will be a useful tool to model the complete SHPB test setup as the incident, reflected and transmitted stress waves can be accurately replicated.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1989 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Steady State Behaviour of Sands and Limitations of the Triaxial Test written by Huiming Zhang and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book General Response of Kneading compacted Unsaturated Silty Sand Under Drained and Undrained True Triaxial Testing written by Sang Chul Pyo and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive series of 36 drained and 36 undrained true triaxial tests was accomplished to investigate the stress-strain-strength behaviour of kneading-compacted unsaturated silty sand (SP-SM) under multi-axial stress states. Test specimens were prepared at three different initial moist contents (6, 8, 10%) to achieve different compaction-induced suction conditions prior to testing. All samples were then subjected to either a drained or undrained multi-axial stress paths, including conventional triaxial compression (CTC), triaxial compression (TC), triaxial extension (TE), or simple shear (SS) stress path. Initial compaction-induced matric suction was assessed via the SWCC of test soil. The experimental program focuses on soil response at high values of suction, that is, within the uppermost vadose zone regime. Test results were plotted in terms of octahedral stress versus principal stress response. Results show that the shear strength of kneading-compacted unsaturated silty sand, regardless of initial compaction-induced suction, increase with an increase in confining pressure. However, as the initial degree of saturation increases from 27 to 61% and the initial dry density increases from 16.4 to 18.1 kN/m3, the ultimate strength of kneading-compacted unsaturated silty sand increases. The undrained soil strength, in most multi-axial stress cases, proved to be slightly higher than that for drained conditions.
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 A Study of the Behaviour of Saturated Sand During Repeated Loading written by Eric Raymond Farrell and published by . This book was released on 1970 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cyclic Stress Conditions Causing Liquefaction of Sand written by Kenneth Lester Lee and published by . This book was released on 1967 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cubical triaxial tests in saturated sand written by and published by . This book was released on 1905 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Este trabalho apresenta um estudo experimental detalhado do comportamento tensão-deformação-resistência de uma areia saturada submetida a uma condição tridimensional de carregamento. Os ensaios foram realizados nos equipamentos triaxiais cúbico e convencional. O equipamento triaxial cúbico apresenta a vantagem de controlar a magnitude das três tensões principais independentemente (sigma 1, sigma 2, sigma 3) sob condições drenada e não drenada. Para o desenvolvimento do trabalho foi utilizada uma amostra de areia calcárea. Os corpos de prova utilizados foram moldados por pluviação submersa. No programa experimental foram realizados ensaios especiais, seguindo diferentestrajetórias de tensão. Este programa foi elaborado de modo a verificar a influência de cada parâmetro de tensão individualmente e os efeitos da anisotropia inicial de areias preparadas por pluviação submersa. Verifica-se através dos resultados de ensaios drenados que as deformações cisalhante e volumétrica são maiores na condição axissimétrica do que na de deformação plana. Tal observação equivale, em solicitações não drenadas, a umacréscimo de poropressão mais acentuado na condição axissimétrica. O comportamento anisotrópico de areias também é revelado com base em ensaios com diferentes direções (alfa) da tensão principal maior. Nos ensaios onde alfa = 90° (direção do carregamento perpendicular à de deposição do solo), ocorrem variações de deformação volumétrica e cisalhante bem mais acentuadas do que para alfa = 0 . O programa experimental mostrou ainda que areias calcáreas não cimentadas não apresentam comportamento tensão-deformação acentuadamente diferente do comportamento de areias de quartzo, mais usuais no Brasil.
Download or read book Geotechnical Abstracts written by and published by . This book was released on 1989 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1988 with total page 728 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Constitutive Relations for Saturated Sand Under Undrained Cyclic Loading written by William G. Pierce and published by . This book was released on 1985 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Stress Path and Prestrain History on the Undrained Monotonic and Cyclic Loading Behaviour of Saturated Sand written by Edwin Kwok Fai Chung and published by . This book was released on 1985 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Liquefaction written by Michael Jefferies and published by CRC Press. This book was released on 2006-09-04 with total page 625 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil liquefaction is a major concern in areas of the world subject to seismic activity or other repeated vibration loads. This book brings together a large body of information on the topic, and presents it within a unified and simple framework. The result is a book which will provide the practising civil engineer with a very sound understanding of
Download or read book Index to American Doctoral Dissertations written by and published by . This book was released on 1989 with total page 1252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
