Download or read book Determination of Potential Vertical Rise in Expansive Soils Using Centrifuge Technology written by Larson Mackenzie Snyder and published by . This book was released on 2015 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt: Expansive soils are a significant issue in Central Texas due to a high potential to shrink and swell which leads to cracking of roadways. A significant amount of research has been conducted on expansive soils, which has led to the development of direct and indirect methods to determine a soil's swelling potential. The methods for direct measurement of the swell potential are typically both time consuming and expensive, which has led to the underutilization these methods. Indirect methods, which use index geotechnical properties to predict the swelling behavior of a soil, are empirically based correlations that are only approximations that don't take into account variables such as the mineralogical composition of the soil and include the Texas Department of Transportation's (TxDOT) approach, Tex-124-E, which is based solely on Atterberg Limits and grain size distributions to determine the potential vertical rise of an expansive deposit beneath a pavement system. The purpose of this study is to develop an approach that both directly measures an expansive soil's swelling potential using centrifuge technology (DMS-C) and determines a potential vertical rise (PVR) for use in site characterization. This study consists of eleven soils sampled from ten sites in Bexar, Atascosa, and Guadalupe Counties of the San Antonio TxDOT district to determine the PVR using the DMS-C and Tex-124-E approaches. Soil characterization tests were conducted including Atterberg Limits and compaction tests, as well as, over 300 specimens tested in the centrifuge testing program. The centrifuge testing program consisted of compacting samples into the double infiltration setup at initial conditions of 3% dry of optimum moisture content and 100% relative compaction and testing the samples at three separate artificial g-levels that correlate to three effective stresses to generate a swell-stress curve that was defined over a range of stresses typically found in the active zone. The results from the centrifuge tests for samples from each site are verified with the traditional free swell tests (ASTM D4546.) At each site, the swell-stress curve and stresses for the soil profile were used to determine the PVR for the DMS-C approach. From the results, seven of the sites received a high or severe degree of concern for potential damage to the pavement. Of these seven sites, six of the sites correlated to soils derived from the Navarro/Marlbrook Formation, which is a major geologic formation in both the San Antonio region as well as the rest of Central Texas east of the Balcones Fault zone. The same stresses, as well as, the liquid limit, plastic limit, and moisture content are used to predict the PVR with the traditional Tex-124-E approach. These results were analyzed and compared to the values to the PVR from the direct measurements taken in the DMS-C approach for each site. From the comparisons, the approximate prediction of PVR for Tex-124-E does not correlate to the direct measurements of swelling results to determine the DMS-C approach. Furthermore, the characterization the swell potential using the centrifuge for PVR calculation with the DMS-C approach was proven to be expeditious and can lead to a significant amount of savings by reducing maintenance and repair of damage. Thus, the DMS-C approach should be implemented into the protocol for the determination of potential vertical rise of expansive soils to more accurately determine whether a given location will be problematic.
Download or read book Potential Vertical Rise of Lime treated Expansive Clays Using Centrifuge Technology written by Karly Ann Summerlin and published by . This book was released on 2018 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Expansive soils are prevalent throughout Central Texas and can cause extensive damage to pavements and other lightweight transportation projects. Methods of directly quantifying soil swell potential are often prohibitively time-consuming, and indirect methods that correlate swell to soil index properties are often based on limited empirical data and ignore variances in soil mineralogy that can significantly affect swell. Soil stabilization or modification, using additives like Portland cement or lime, is often utilized to mitigate the effects of expansive soil. In particular, the Texas Department of Transportation (TxDOT) recommends lime treatment for highly plastic soils below many transportation projects. However, many common design procedures do not directly measure the swell potential of the lime-treated soils and rather rely on methods like the Eades-Grim pH test to determine dosage. Additionally, design procedures do not often include a method for determining project-specific treatment depths. This research seeks to develop a procedure for directly quantifying the swell of lime-treated soils such that a project-specific treatment depth and dosage may be prescribed. Centrifuge tests performed on Eagle Ford clay were used to assess the effects of the testing procedure on swell results. It was determined that mellowing lime-treated soil samples did not significantly affect their swell potential but did increase soil workability. Additionally, curing of lime-treated soil samples decreased swell for samples treated with 4% by dry mass hydrated lime after curing for at least 6 weeks, but curing for any time did not decrease swell for samples treated with 2% hydrated lime. It was concluded that lime-treated swell testing could be optimally performed on uncured samples that were allowed to mellow for 12-24 hours to maximize workability. The reduced testing procedure for directly calculating an untreated and lime-treated soil potential vertical rise (PVR) recommends obtaining 3 data points across a representative range of stresses for each distinct layer of untreated soil in a given stratum, which is fit to a semi-log linear curve. One data point is used for each lime dosage to be tested, and the approximation of a unique soil swell pressure is used to produce a semi-log linear stress-swell curve from each of these points. The area under each curve for the stress range in question is then used to calculate the PVR of a soil profile. PVR analyses on two sites from San Antonio in Bexar County, Texas show that the assumption of log-linear stress-swell curves and the approximation of a constant swell pressure return PVR calculations that are similar to those calculated from stress-swell curves that require more parameters and more data points to propagate.
Download or read book Characterization of the Swelling Behavior of Expansive Clays Using Centrifuge Technology written by Nicolas Alejandro Rivas and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental techniques with emphasis in centrifuge testing were implemented to characterize the swelling behavior of expansive clays. This research consisted in three self-contained sections related to the study of different aspects of expansive clays. The first research component focused on the implementation of a qualitative mineralogy analysis performed using x-ray diffraction to determine the main clay minerals in an expansive soil. The analysis was performed on the clay-sized fraction of the soil and samples with preferential and random orientation were used in the analysis. Vacuum filtration was used to produce oriented samples in order to maximize the intensity of the diagnostic basal spacing of the clay minerals, and samples were subjected to different treatments to produce changes in the basal spacing or crystalline structure of the clay minerals to facilitate their identification. The second research component examined the effect of the coarse fraction on the swelling characteristics of expansive soils using a centrifuge-based approach. Vertical strains at the end of primary swelling were evaluated for different proportions of coarse fraction by volume. It was found that the magnitude of vertical strains at the end of primary swelling decreased with increasing coarse fraction. It was concluded that the swelling depended uniquely on the ratio between the volume of soil solids of the fine fraction and the volume of voids. Additionally, when correcting the initial void ratio of the specimens to account for this, the relationship between vertical strains at the end of primary swelling and initial void ratio for the soil mixtures defines a unique linear trend with the baseline material. The third research component examined the potential vertical rise at three field sites in Central Texas. Method 6048-A was applied to evaluate the PVR of three field sites using direct measurements of the swelling characteristics of soils sampled at each location. Project-specific data was generated in a relatively short time using this centrifuge-based method. The results obtained demonstrated the need for testing of project-specific samples, as a significant variation in PVR was observed in Site 2 and 3 between boring locations, while less variation between borings was found in Site 1
Download or read book From Research to Applied Geotechnics written by N.P. López-Acosta and published by IOS Press. This book was released on 2019-11-26 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first Pan-American Conference on Soil Mechanics and Geotechnical Engineering (PCSMGE) was held in Mexico in 1959. Every 4 years since then, PCSMGE has brought together the geotechnical engineering community from all over the world to discuss the problems, solutions and future challenges facing this engineering sector. Sixty years after the first conference, the 2019 edition returns to Mexico. The XVI PCSMGE 2019 conference was held in Cancun, Mexico, from 17 – 20 November 2019. This book presents the plenary lectures from the conference, delivered by distinguished geotechnical engineers of international renown. Experience and youth combine in this special publication, which includes the 9th Arthur Casagrande lecture, the plenary lecture of the ISSMGE President, 3 Bright Spark lectures, and the manuscripts of the 13 invited lecturers of practically all the technical sessions at the XVI PCSMGE 2019. Topics cover both research and applied geotechnics, including recent developments in geotechnical engineering. Representing a valuable reference for engineering practitioners and graduate students, and helping to identify new issues and shape future directions for research, the book will be of interest to all those working in the field, involved in soil mechanics and geotechnical engineering.
Download or read book Expansive Soils written by Amer Ali Al-Rawas and published by CRC Press. This book was released on 2006-06-08 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: Expansive Soils provides the reader with easy and specific access to problems associated with expansive soils, characterisitics and treatment, and evaluation and remediation. Set up with contributions from worlwide expert, this main reference guide is intended for engineers, researchers and senior students working on soil
Download or read book Geotechnical Centrifuge Technology written by R.N. Taylor and published by CRC Press. This book was released on 2003-09-02 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a thorough review of this powerful and sophisticated technique for modelling soil structure interactions. It has been written by an international team of authors.
Download or read book Plant Soil Slope Interaction written by Charles Wang Wai Ng and published by CRC Press. This book was released on 2019-07-01 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: This inter-disciplinary book provides the latest advanced knowledge of plant effects on vegetated soil properties such as water retention capability, water permeability function, shear strength, slope hydrology, movements and failure mechanisms, and applies this knowledge to the solution of slope stability problems. It is the first book to cover in detail not only the mechanical effects of root reinforcement but more importantly the hydrological effects of plant transpiration on soil suction, soil shear strength, and water permeability. The book also offers a fundamental understanding of soil-plant-water interaction. Analytical equations are provided for predicting the combined hydrological and mechanical effects of plant roots on slope stability. A novel method is also given for simulating transpiration-induced suction in a geotechnical centrifuge. Application of this method to the study of the failure mechanisms of vegetated slopes reinforced by roots with different architectures is discussed. This book is essential reading for senior undergraduate and postgraduate students as well as researchers in civil engineering, geo-environmental engineering, plant ecology, agricultural science, hydrology and water resources. It also provides advanced knowledge for civil engineers seeking "green" engineering solutions to combat the negative impact of climate change on the long-term engineering sustainability of infrastructure slopes. Professionals other than civil engineers, such as ecologists, agriculturists, botanists, environmentalists, and hydrologists, would also find the book relevant and useful.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1987 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geo frontiers 2011 written by and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Deep Mixing Method written by Masaki Kitazume and published by CRC Press. This book was released on 2013-02-21 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Deep Mixing Method (DMM), a deep in-situ soil stabilization technique using cement and/or lime as a stabilizing agent, was developed in Japan and in the Nordic countries independently in the 1970s. Numerous research efforts have been made in these areas investigating properties of treated soil, behavior of DMM improved ground under static and d
Download or read book Modeling in Geotechnical Engineering written by Pijush Samui and published by Academic Press. This book was released on 2020-12-01 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modeling in Geotechnical Engineering is a one stop reference for a range of computational models, the theory explaining how they work, and case studies describing how to apply them. Drawing on the expertise of contributors from a range of disciplines including geomechanics, optimization, and computational engineering, this book provides an interdisciplinary guide to this subject which is suitable for readers from a range of backgrounds. Before tackling the computational approaches, a theoretical understanding of the physical systems is provided that helps readers to fully grasp the significance of the numerical methods. The various models are presented in detail, and advice is provided on how to select the correct model for your application. - Provides detailed descriptions of different computational modelling methods for geotechnical applications, including the finite element method, the finite difference method, and the boundary element method - Gives readers the latest advice on the use of big data analytics and artificial intelligence in geotechnical engineering - Includes case studies to help readers apply the methods described in their own work
Download or read book Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering written by The Organizing Committee of the 16th ICSMGE and published by IOS Press. This book was released on 2005-09-12 with total page 3742 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 16th ICSMGE responds to the needs of the engineering and construction community, promoting dialog and exchange between academia and practice in various aspects of soil mechanics and geotechnical engineering. This is reflected in the central theme of the conference 'Geotechnology in Harmony with the Global Environment'. The proceedings of the conference are of great interest for geo-engineers and researchers in soil mechanics and geotechnical engineering. Volume 1 contains 5 plenary session lectures, the Terzaghi Oration, Heritage Lecture, and 3 papers presented in the major project session. Volumes 2, 3, and 4 contain papers with the following topics: Soil mechanics in general; Infrastructure and mobility; Environmental issues of geotechnical engineering; Enhancing natural disaster reduction systems; Professional practice and education. Volume 5 contains the report of practitioner/academic forum, 20 general reports, a summary of the sessions and workshops held during the conference.
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 Expansive Soils written by John Nelson and published by John Wiley & Sons. This book was released on 1997-02-13 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essential technical information for building on expansive soils--complete with practical, proven design methods. Expansive Soils examines factors that influence the design offoundations and pavements built on expansive soils, and exploreskey design procedures and remedial measures that address thesefactors effectively. Backed by the authors' extensive research andexperience --including interviews with practicing engineers workingwith expansive soils --this authoritative volume is an importantreference text for geotechnical and foundation engineers,geologists, construction professionals, and students. Easy to understand and apply, Expansive Soils contains: * Site investigation techniques for identification andclassification of expansive soils * Heave prediction methods using different types of data --withrigorous treatment of soil suction theory and measurement,oedometer tests, and more * Alternative design procedures for drilled pier and slab-on-gradefoundations, highway and airfield pavements * Treatment and chemical stabilization techniques --including salttreatment; moisture barriers; lime and cement stabilization; andother procedures * Remedial measures such as drainage control, and removal withreplacement and compaction control * Sample problems illustrating practical applications.
Download or read book Geotechnical Abstracts written by and published by . This book was released on 1986 with total page 862 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Mechanics Design written by United States. Army. Corps of Engineers and published by . This book was released on 1953 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Foundations on Expansive Soils written by Fu Hua Chen and published by Elsevier. This book was released on 2012-12-02 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: Foundations on Expansive Soils provides the practicing engineer with a summary of the state-of-the-art of expansive soils and practical solutions based on the author's experience. The book is organized into two parts. Part I deals with theory and practice, and summarizes some of the theoretical physical properties of expansive soils. It also discusses various techniques employed to found structures on expansive soils such as drilled pier foundation, mat foundation, moisture control, soil replacement, and chemical stabilization. Topics covered include the origin, mineralogical composition, and the basic structure of expansive soils; the migration of water, swelling potential, and swelling pressure; site investigations and laboratory testing; moisture control; and soil stabilization. Part II presents case studies on the following: distress caused by pier uplift; distress caused by the improper design and construction of a drilled pier foundation system; distress caused by heaving of footing pad and floor slab; distress caused by heaving of continuous footings; and distress caused by a rise of ground water.
