Download or read book Effect of Different Modes of Lateral Boundary Constraints of the Direct Simple Shear DSS Device Under Monotonic and Cyclic Shear Loading written by Priyesh Verma and published by . This book was released on 2020 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geological Disasters in Deep Engineering Mechanism Warning and Risk Mitigation Volume II written by Guang-Liang Feng and published by Frontiers Media SA. This book was released on 2023-10-26 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Automatic Static and Cyclic Shear Testing Machine Under Constant Normal Stiffness Boundary Conditions written by S. M. Mahdi Niktabar and published by . This book was released on 2018 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic loads, including earthquake, blasting, and vibration loads, induce cyclic shear loads along the joints in rock masses; hence, the risk of failure increases on the joints due to changing shear resistance. On the other hand, joints are under different boundary conditions: constant normal load (CNL) and constant normal stiffness (CNS). Normal stiffness increases on the joints with increasing depth, and it can affect shear resistance. For an accurate assessment of joint shear resistance under varying normal stiffness and number of cycles, advanced laboratory shear apparatus is essential for the shear test. Conventional direct shear apparatuses have limitations such as boundary conditions, working under monotonic (static) shear loads only, or cyclic shear loads with no change of frequency and amplitude of shear loads. Therefore, a new large-scale servo-controlled direct shear testing machine was developed to conduct cyclic shear test (as well as monotonic shear test) under CNL and CNS boundary conditions with varying normal stiffness at different frequencies and amplitudes of shear loads. In the present study, the cyclic shear tests were conducted on nonplanar joints under varying normal stiffness. Moreover, the effects of different frequencies and amplitudes of shear loads were investigated. The test results indicate that peak shear stress increases with increasing normal stiffness at the first cycle, but the influence of normal stiffness decreases with an increase in the number of shear cycles. The frequency of shear load influences peak shear stress, i.e., peak shear stress increases with increasing frequency. The number of cycles does not affect peak shear stress on the joints at low shear amplitude, but peak shear stress decreases with higher amplitude.
Download or read book Evaluating Impact of Various Direct Simple Shear Machine Compliances on Constant Volume Cyclic Strength of Nevada Sand written by Gina Nicolle Espinosa and published by . This book was released on 2019 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results from cyclic direct simple shear tests are presented in this thesis. The tests were performed under undrained constant volume conditions using Nevada Sand to evaluate the effectiveness of the recent modifications on reducing the impact of machine compliance (particularly, in terms of vertical deformations during shearing) on the results. The specimens were reconstituted with the water sedimentation technique at two relative densities: loose and dense. Furthermore, the cyclic resistance responses for dense and loose specimens are presented, including a detailed analysis of the various measured axial deformations to determine their impact on the results. Measuring axial strains during shearing is critical for tests sheared under constant volume conditions. For such tests to be considered undrained, the volumetric change and, therefore the axial strains, should not exceed 0.05% as stated by ASTM D6528-17. The results from a range of tests showed that some axial strains measures, like the average of the peak-to-peak axial strains and the difference and the average of the axial strain slopes, reflected more accurately what occurred while shearing the specimens. The average peak-to-peak axial strain captured the rocking or tilting behavior while the difference in axial strain slopes showed that at higher CSRs, higher bending is observed in the equipment, and therefore higher distortions in the specimens resulting in a lower number of cycles to liquefaction. The improvements to the equipment showed a major decrease in rocking, particularly at the level of the bottom plate of the 4-piston assembly. This resulted in a 10-times decrease in the rocking at the platen level. However, there is still some more room for improvement to further lower the rocking through a more rigid connection between the top platen and the load cell. The screw-nut jacks worked well in locking the top platen in place and minimizing vertical displacements during shearing. The larger jacks and higher torques results in lower vertical strains, up to 20 times lower than the current recommendations of 0.05%. Lastly, the modifications resulted in a much stiffer system for resisting the lateral forces with minimal horizontal displacement in the top platen, and thus eliminating the major drawback of the old system
Download or read book A New Cyclic Simple Shear Test Procedure with Multidirectional Loading written by Viet Hung Le and published by . This book was released on 2020 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: This article presents a new procedure for cyclic simple shear tests with a change in the loading direction. For the experimental investigation of sand under drained condition, a conventional simple shear test device (unidirectional simple shear) was used. After modification of the specimen cell, the cell can rotate during the test, enabling the load direction to be changed. The construction of this modified version and its test procedure are explained in detail. This modification and test procedure can also be used for different simple shear devices of the same type. Furthermore, a test series involving Berlin sand was conducted with the direction of cyclic loading being changed once during each test. The test results indicate that a change in the cyclic direction has a significant influence on the accumulated deformation of sand.
Download or read book Some Observations on the State of Stress in the Direct Simple Shear Test Using 3D Discrete Element Analysis written by Dharma Wijewickreme and published by . This book was released on 2013 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Assessment of the mobilized friction angle in a soil specimen tested in a given shear apparatus requires adequate information to establish the stress state at the instance of interest. In the most commonly used version of the direct simple shear (DSS) apparatus, where a cylindrical soil specimen is confined by wire-reinforced membrane, only the normal and shear stresses on the horizontal plane are measured. The knowledge of these stresses alone does not provide adequate information to construct the Mohr circle defining the state of stress. In this context, drained and constant volume (i.e., equivalent to undrained) discrete element simulations of a cylindrical DSS specimen were performed and the results are presented with emphasis on the DSS mobilized friction angle during shearing. It was found that planes of maximum stress obliquity rotate with the development of shear strain. This finding implies that it is not possible to calculate the friction angle accurately from typical DSS laboratory tests with unknown normal stress on the vertical plane. However, it seems that at large shear strains, the horizontal plane becomes a plane of maximum stress obliquity, and the friction angle calculated using the stress state on the horizontal plane is a good approximation to the mobilized friction angle at such shear strain levels.
Download or read book Finite Element Analysis in Geotechnical Engineering written by David M Potts and published by Thomas Telford. This book was released on 2001 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: An insight into the use of the finite method in geotechnical engineering. The first volume covers the theory and the second volume covers the applications of the subject. The work examines popular constitutive models, numerical techniques and case studies.
Download or read book Frontiers in Offshore Geotechnics III written by Vaughan Meyer and published by CRC Press. This book was released on 2015-05-15 with total page 1422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Frontiers in Offshore Geotechnics III comprises the contributions presented at the Third International Symposium on Frontiers in Offshore Geotechnics (ISFOG, Oslo, Norway, 10-12 June 2015), organised by the Norwegian Geotechnical Institute (NGI). The papers address current and emerging geotechnical engineering challenges facing those working in off
Download or read book Evaluation of Soil and Rock Properties written by P. J. Sabatini and published by . This book was released on 2004-10-01 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document presents state-of-the-practice information on the evaluation of soil and rock properties for geotechnical design applications. This document addresses the entire range of materials potentially encountered in highway engineering practice, from soft clay to intact rock and variations of materials that fall between these two extremes. Information is presented on parameters measured, evaluation of data quality, and interpretation of properties for conventional soil and rock laboratory testing, as well as in situ devices such as field vane testing, cone penetration testing, dilatometer, pressuremeter, and borehole jack. This document provides the design engineer with information that can be used to develop a rationale for accepting or rejecting data and for resolving inconsistencies between data provided by different laboratories and field tests. This document also includes information on: (1) the use of Geographical Information Systems (GIS) and Personal Data Assistance devices for the collection and interpretation of subsurface information; (2) quantitative measures for evaluating disturbance of laboratory soil samples; and (3) the use of measurements from geophysical testing techniques to obtain information on the modulus of soil. Also included are chapters on evaluating properties of special soil materials (e.g., loess, cemented sands, peats and organic soils, etc.) and the use of statistical information in evaluating anomalous data and obtaining design values for soil and rock properties. An appendix of three detailed soil and rock property selection examples is provided which illustrate the application of the methods described in the document.
Download or read book Recent Advances and Applications of Hybrid Simulation written by Wei Song and published by Frontiers Media SA. This book was released on 2021-01-13 with total page 213 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 Geomechanics from Micro to Macro written by Kenichi Soga and published by CRC Press. This book was released on 2014-08-26 with total page 1668 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geomechanics from Micro to Macro contains 268 papers presented at the International Symposium on Geomechanics from Micro and Macro (IS-Cambridge, UK, 1-3 September 2014). The symposium created a forum for the dissemination of new advances in the micro-macro relations of geomaterial behaviour and its modelling. The papers on experimental investigati
Download or read book Recent Developments of Soil Mechanics and Geotechnics in Theory and Practice written by Theodoros Triantafyllidis and published by Springer Nature. This book was released on 2019-08-20 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides essential insights into recent developments in fundamental geotechnical engineering research. Special emphasis is given to a new family of constitutive soil description methods, which take into account the recent loading history and the dilatancy effects. Particular attention is also paid to the numerical implementation of multi-phase material under dynamic loads, and to geotechnical installation processes. In turn, the book addresses implementation problems concerning large deformations in soils during piling operations or densification processes, and discusses the limitations of the respective methods. Numerical simulations of dynamic consolidation processes are presented in slope stability analysis under seismic excitation. Lastly, achieving the energy transition from conventional to renewable sources will call for geotechnical expertise. Consequently, the book explores and analyzes a selection of interesting problems involving the stability and serviceability of supporting structures, and provides new solutions approaches for practitioners and scientists in geotechnical engineering. The content reflects the outcomes of the Colloquium on Geotechnical Engineering 2019 (Geotechnik Kolloquium), held in Karlsruhe, Germany in September 2019.
Download or read book Dynamic Geotechnical Testing written by M. L. Silver and published by ASTM International. This book was released on 1978 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geo Congress 2013 Stability and Performance of Slopes and Embankments III written by Christopher L. Meehan and published by . This book was released on 2013-03-01 with total page 2280 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Geotechnical Special Publication contains 229 peer-reviewed technical papers and case studies focusing on the stability, performance, and rehabilitation of slopes, embankments, and dams. Topics include: exploration and characterisation of soil and rock slopesdesign, analysis, and performance of slopesmonitoring and inspection of slopeshazard assessment and managementground improvement and stabilisation in the repair and remediation of slopes. These papers are valuable to geotechnical researchers and practicing engineers, especially those interested in the design and maintenance of slopes, embankments and dams.
Download or read book Physical Modelling in Geotechnics Volume 1 written by Andrew McNamara and published by CRC Press. This book was released on 2018-07-11 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physical Modelling in Geotechnics collects more than 1500 pages of peer-reviewed papers written by researchers from over 30 countries, and presented at the 9th International Conference on Physical Modelling in Geotechnics 2018 (City, University of London, UK 17-20 July 2018). The ICPMG series has grown such that two volumes of proceedings were required to publish all contributions. The books represent a substantial body of work in four years. Physical Modelling in Geotechnics contains 230 papers, including eight keynote and themed lectures representing the state-of-the-art in physical modelling research in aspects as diverse as fundamental modelling including sensors, imaging, modelling techniques and scaling, onshore and offshore foundations, dams and embankments, retaining walls and deep excavations, ground improvement and environmental engineering, tunnels and geohazards including significant contributions in the area of seismic engineering. ISSMGE TC104 have identified areas for special attention including education in physical modelling and the promotion of physical modelling to industry. With this in mind there is a special themed paper on education, focusing on both undergraduate and postgraduate teaching as well as practicing geotechnical engineers. Physical modelling has entered a new era with the advent of exciting work on real time interfaces between physical and numerical modelling and the growth of facilities and expertise that enable development of so called ‘megafuges’ of 1000gtonne capacity or more; capable of modelling the largest and most complex of geotechnical challenges. Physical Modelling in Geotechnics will be of interest to professionals, engineers and academics interested or involved in geotechnics, geotechnical engineering and related areas. The 9th International Conference on Physical Modelling in Geotechnics was organised by the Multi Scale Geotechnical Engineering Research Centre at City, University of London under the auspices of Technical Committee 104 of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE). City, University of London, are pleased to host the prestigious international conference for the first time having initiated and hosted the first regional conference, Eurofuge, ten years ago in 2008. Quadrennial regional conferences in both Europe and Asia are now well established events giving doctoral researchers, in particular, the opportunity to attend an international conference in this rapidly evolving specialist area. This is volume 1 of a 2-volume set.
Download or read book Manufacturing and Application of Stainless Steels written by Andrea Di Schino and published by MDPI. This book was released on 2020-04-15 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stainless steels represent a quite interesting material family, both from a scientific and commercial point of view, following to their excellent combination in terms of strength and ductility together with corrosion resistance. Thanks to such properties, stainless steels have been indispensable for the technological progress during the last century and their annual consumption increased faster than other materials. They find application in all these fields requiring good corrosion resistance together with ability to be worked into complex geometries. Despite to their diffusion as a consolidated materials, many research fields are active regarding the possibility to increase stainless steels mechanical properties and corrosion resistance by grain refinement or by alloying by interstitial elements. At the same time innovations are coming from the manufacturing process of such a family of materials, also including the possibility to manufacture them starting from metals powder for 3D printing. The Special Issue scope embraces interdisciplinary work covering physical metallurgy and processes, reporting about experimental and theoretical progress concerning microstructural evolution during processing, microstructure-properties relations, applications including automotive, energy and structural.
