Download or read book Performance of Soil Moisture Characteristic Curves for Diverse Soils written by D. Akins and published by . This book was released on 1992 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ground Improvement written by Professor Jian Chu and published by Elsevier. This book was released on 2005-11-07 with total page 1137 pages. Available in PDF, EPUB and Kindle. Book excerpt: - The first book of its kind, providing over thirty real-life case studies of ground improvement projects selected by the worlds top experts in ground improvement from around the globe. - Volume 3 of the highly regarded Elsevier Geo-engineering book series coordinated by the Series Editor: Professor John A Hudson FREng. - An extremely reader friendly chapter format. - Discusses wider economical and environmental issues facing scientists in the ground improvement.Ground improvement has been both a science and art, with significant developments observed through ancient history. From the use of straw as blended infill with soils for additional strength during the ancient Roman civilizations, and the use of elephants for compaction of earth dams during the early Asian civilizations, the concepts of reinforced earth with geosynthetics, use of electrokinetics and thermal modifications of soils have come a long way. The use of large and stiff stone columns and subsequent sand drains in the past has now been replaced by quicker to install and more effective prefabricated vertical drains, which have also eliminated the need for more expensive soil improvement methods.The early selection and application of the most appropriate ground improvement techniques can improve considerably not only the design and performance of foundations and earth structures, including embankments, cut slopes, roads, railways and tailings dams, but also result in their cost-effectiveness. Ground improvement works have become increasingly challenging when more and more problematic soils and marginal land have to be utilized for infrastructure development.This edited compilation contains a collection of Chapters from invited experts in various areas of ground improvement, who have illustrated the basic concepts and the applications of different ground improvement techniques using real projects that they have been involved in. The case histories from many countries ranging from Asia, America, Australia and Europe are addressed.
Download or read book Measurements and Transient Multistep Outflow Simulation of Soil water Characteristic Curve for Soils Modified with Biopolymers written by Xiaoyi Zhao and published by . This book was released on 2014 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In recent decades, biopolymers have shown promising applications in soil modification due to its environmental friendly nature. Most of the studies, however, focused on mechanical properties at saturated or unsaturated conditions. The study on unsaturated soil behaviors under controlled pore air and pore water pressures were limited. Soil-water characteristic curve (SWCC), relating water content with matric suction is a key property to evaluate unsaturated soils. With SWCC, other soil properties, such as hydraulic conductivity and shear strength can be estimated. In this study, SWCC of sands modified with different biopolymers were measured with both Tempe cell and Fredlund SWCC device. An elevation-controlled low suction (0.01 to 5 kPa) horizontal tube was developed to accurately measure SWCC of sands. Corrections for air diffusion and evaporation were performed. The results were fitted by both Fredlund and Xing and van Genutchen equations. In addition, inverse simulation of SWCC based on one-step or multistep SWCC measurements were carried out with software Hydrus 1D, finite element software. The measured SWCC results of mine tailing were used as an example. The inverse model can significantly reduce the time to measure a SWCC curve, especially for soils with low hydraulic conductivity (clay and silt). Three different input outflow methods were used, namely multiple single-step outflow method (MSOM), one-step outflow method (OOM), and multiple-step outflow method (MOM). Their performance was evaluated by both SWCC results and outflow vs. time curves. It was found that MOM provided the most accurate SWCC, while MSOM yielded the most accurate Flux -Time results"--Abstract, page iii.
Download or read book Soil Water Characteristics of Sandy Soil and Soil Cement with and Without Vegetation written by Guanghui Zhang and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Soil-water Characteristics of Sandy Soil and Soil Cement With and Without Vegetation" by Guanghui, Zhang, 張廣輝, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: The use of soil cement as a growth medium was examined in this study. During the monitoring, green soil cement revealed diverse ecological values. The survival rates of plants in each soil conditions were higher than 80%, which was very promising. Furthermore, the survival rates dropped when the soil density reached95%, which means soil density might influence the survival rate of plant. Plant growth rates in sandy soil were higher than that in soil cement. In particular, low soil density facilitated plant growth in sandy soil, whereas density effect was not clear to plant growth performance in soil cement. Experiments were undertaken to study the soil-water characteristics of sandy soil and soil cement in field and laboratory condition. The influence of vegetation and material density on the development of negative pore water pressure (PWP) and degree of saturation (Sr) in the studied materials was investigated. The field planting experiments proved a promising survival rate of Schefflera heptaphylla in both types of materials while sandy soil promoted better growth of the seedlings than the soil cement. From the field study, PWP and Sr of sandy soil responded noticeably and promptly to natural drying and wetting cycles. However, the responses in soil cement were relatively mild. When subjected to the same drying-wetting cycles, PWP responded more slowly and to a smaller magnitude compared with that of soil cement. In addition, Sr changed little in soil cement. An increase in the density of the sandy soil promoted rapid development of negative PWP, while an opposite trend was observed for soil cement. Attempts have been made to explain the observations from the perspectives of material permeability and change in water content during a drying period in both soil types. Furthermore, in sandy soil, the development of PWP (with a measurement limit of -90 kPa) was minimally affected by the presence of vegetation, while vegetation noticeably helped the development of negative PWP in the soil cement. Bounds of the soil-water characteristic curve of the studied materials were presented based on estimates from the drying and wetting scanning curves derived from the field monitoring. A complementary laboratory study was carried out in an environmental chamber with controllable temperature and humidity. Monitoring results from the laboratory agreed well with that obtained from the field. DOI: 10.5353/th_b5351048 Subjects: Soil moisture Sandy soils Soil cement
Download or read book Development of Pedotransfer Functions in Soil Hydrology written by Yakov Pachepsky and published by Elsevier. This book was released on 2004-12-30 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental and agricultural modeling and assessment have a multitude of uses for soil parameters governing retention and transport of water and chemicals in soils. These parameters are notorious for the difficulties and high labor costs involved in measuring them. Good estimates instead of direct measurements may be accurate enough for many applications. Pedotransfer functions provide such estimates by utilizing available soil survey information to translate data we have into data we need. This book is the first book on the topic. It provides the unique compendium of pedotransfer functions, summarizes the vast international experience in this field, and shows how the value of soil data can be increased by using them in pedotransfer functions to predict soil hydrologic and related properties. The book is a rich source of information crucial for environmental research and applications.
Download or read book Soil Mechanics for Unsaturated Soils written by Delwyn G. Fredlund and published by John Wiley & Sons. This book was released on 1993-09-06 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt: The principles and concepts for unsaturated soils are developed as extensions of saturated soils. Addresses problems where soils have a matric suction or where pore-water pressure is negative. Covers theory, measurement and use of the fundamental properties of unsaturated soils--permeability, shear strength and volume change. Includes a significant amount of case studies.
Download or read book Significance of Soil Suction and Soil Water Characteristic Curve Parameters written by GL. Sivakumar Babu and published by . This book was released on 2005 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil Water Characteristic Curves (SWCC) of unsaturated soils have considerable importance in analysis of geotechnical engineering problems. In these analyses, it is necessary to make a distinction between the components of total suction in terms of solute and matric suctions, which is generally ignored in practice. In the present study, suction characteristics of two compacted clayey soils are measured using filter paper method (ASTM D 5298-94), which is useful in this regard. The experimental results show that consideration of only matric suction instead of total suction is conservative as it constitutes about 25 to 60% of total suction in clay soils. Theoretical models were fitted to experimental results, and it is demonstrated that the model parameters are different in terms of total suction and matric suction. The results show that measurement of both the components of suction using the filter paper method is simple and useful in engineering analysis.
Download or read book Unsaturated Flow in Hydrologic Modeling written by H.J. Morel-Seytoux and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume certainly is a Conference Proceedings, the Proceedings of the NATO Advanced Research Workshop (ARW) on "Unsaturated Flow in Hydrologic Modeling" held at "Les Villages du Soleil" near ArIes, France from June 13 to 17, 1988. Let me therefore acknowledge properly, at the very beginning, the gratitude of all the participants to the NATO Science Committee for its generous support and worthwhile goal of bringing together scientists of many countries to communicate and share their experiences. Particular thanks are extended to the director of the program, Dr. Luis Vega da Cunha for his interest and understanding. On the other hand this volume is also, and probably more so, a Textbook that fills a gap in the field of unsaturated flow. Many treatises on the subject present the theory in its different aspects. Hardly any explain in details how the different pieces can be put together to address realistic problems at the basin scale. The various invited contributions to the ARW were structured in a subject progression much as chapters are organized in a book. The intent of the ARW was to assess the current state of knowledge in "Unsaturated Flow" and its use in "Hydrologic Modeling Practice". In a sense the interest in fundamentals of unsaturated flow in this ARW was not just for the sake of knowledge but also and primarily for the sake of action. Can such fundamental knowledge be utilized for better management of the water resource? was the basic question.
Download or read book Soil Water Characteristic Curves for Compacted Fine grained Soils written by James Martin Tinjum and published by . This book was released on 1995 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Unsaturated Soil Mechanics written by Ning Lu and published by John Wiley & Sons. This book was released on 2004-05-20 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unsaturated Soil Mechanics is the first book to provide a comprehensive introduction to the fundamental principles of unsaturated soil mechanics. * Offers extensive sample problems with an accompanying solutions manual. * Brings together the rapid advances in research in unsaturated soil mechanics in one focused volume. * Covers advances in effective stress and suction and hydraulic conductivity measurement.
Download or read book Estimating the Soil water Characteristic Curve Using Grain Size Analysis and Plasticity Index written by Gustavo Torres Hernandez and published by . This book was released on 2011 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: The infrastructure is built in Unsaturated Soils. However, the geotechnical practitioners insist in designing the structures based on Saturated Soil Mechanics. The design of structures based on unsaturated soil mechanics is desirable because it reduces cost and it is by far a more sustainable approach. The research community has identified the Soil-Water Characteristic Curve as the most important soil property when dealing with unsaturated conditions. This soil property is unpopular among practitioners because the laboratory testing takes an appreciable amount of time. Several authors have attempted predicting the Soil-Water Characteristic Curve; however, most of the published predictions are based on a very limited soil database. The National Resources Conservation Service has a vast database of engineering soil properties with more than 36,000 soils, which includes water content measurements at different levels of suctions. This database was used in this study to validate two existing models that based the Soil-Water Characteristic Curve prediction on statistical analysis. It was found that although the predictions are acceptable for some ranges of suctions; they did not performed that well for others. It was found that the first model validated was accurate for fine-grained soils, while the second model was best for granular soils. For these reasons, two models to estimate the Soil-Water Characteristic Curve are proposed. The first model estimates the fitting parameters of the Fredlund and Xing (1994) function separately and then, the predicted parameters are fitted to the Fredlund and Xing function for an overall estimate of the degree of saturation. Results show an overall improvement on the predicted values when compared to existing models. The second model is based on the relationship between the Soil-Water Characteristic Curve and the Pore-Size Distribution of the soils. The process allows for the prediction of the entire Soil-Water Characteristic Curve function and proved to be a better approximation than that used in the first attempt. Both models constitute important tools in the implementation of unsaturated soil mechanics into engineering practice due to the link of the prediction with simple and well known engineering soil properties.
Download or read book Unsaturated Soil Mechanics in Engineering Practice written by Delwyn G. Fredlund and published by John Wiley & Sons. This book was released on 2012-07-30 with total page 946 pages. Available in PDF, EPUB and Kindle. Book excerpt: The definitive guide to unsaturated soil— from the world's experts on the subject This book builds upon and substantially updates Fredlund and Rahardjo's publication, Soil Mechanics for Unsaturated Soils, the current standard in the field of unsaturated soils. It provides readers with more thorough coverage of the state of the art of unsaturated soil behavior and better reflects the manner in which practical unsaturated soil engineering problems are solved. Retaining the fundamental physics of unsaturated soil behavior presented in the earlier book, this new publication places greater emphasis on the importance of the "soil-water characteristic curve" in solving practical engineering problems, as well as the quantification of thermal and moisture boundary conditions based on the use of weather data. Topics covered include: Theory to Practice of Unsaturated Soil Mechanics Nature and Phase Properties of Unsaturated Soil State Variables for Unsaturated Soils Measurement and Estimation of State Variables Soil-Water Characteristic Curves for Unsaturated Soils Ground Surface Moisture Flux Boundary Conditions Theory of Water Flow through Unsaturated Soils Solving Saturated/Unsaturated Water Flow Problems Air Flow through Unsaturated Soils Heat Flow Analysis for Unsaturated Soils Shear Strength of Unsaturated Soils Shear Strength Applications in Plastic and Limit Equilibrium Stress-Deformation Analysis for Unsaturated Soils Solving Stress-Deformation Problems with Unsaturated Soils Compressibility and Pore Pressure Parameters Consolidation and Swelling Processes in Unsaturated Soils Unsaturated Soil Mechanics in Engineering Practice is essential reading for geotechnical engineers, civil engineers, and undergraduate- and graduate-level civil engineering students with a focus on soil mechanics.
Download or read book Metaheuristics in Water Geotechnical and Transport Engineering written by Xin-She Yang and published by Newnes. This book was released on 2012-09 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to an ever-decreasing supply in raw materials and stringent constraints on conventional energy sources, demand for lightweight, efficient and low cost structures has become crucially important in modern engineering design. This requires engineers to search for optimal and robust design options to address design problems that are often large in scale and highly nonlinear, making finding solutions challenging. In the past two decades, metaheuristic algorithms have shown promising power, efficiency and versatility in solving these difficult optimization problems. This book examines the latest developments of metaheuristics and their applications in water, geotechnical and transport engineering offering practical case studies as examples to demonstrate real world applications. Topics cover a range of areas within engineering, including reviews of optimization algorithms, artificial intelligence, cuckoo search, genetic programming, neural networks, multivariate adaptive regression, swarm intelligence, genetic algorithms, ant colony optimization, evolutionary multiobjective optimization with diverse applications in engineering such as behavior of materials, geotechnical design, flood control, water distribution and signal networks. This book can serve as a supplementary text for design courses and computation in engineering as well as a reference for researchers and engineers in metaheursitics, optimization in civil engineering and computational intelligence. Provides detailed descriptions of all major metaheuristic algorithms with a focus on practical implementation Develops new hybrid and advanced methods suitable for civil engineering problems at all levels Appropriate for researchers and advanced students to help to develop their work
Download or read book The Temperature Dependence of Soil moisture Characteristics of Agricultural Soils written by Amir Salehzadeh and published by . This book was released on 1990 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Unsaturated Soils Two Volume Set written by Eduardo E. Alonso and published by CRC Press. This book was released on 2010-09-02 with total page 1532 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent decades the development of unsaturated soil mechanics has been remarkable, resulting in momentous advances in fundamental knowledge, testing techniques, computational procedures, prediction methodologies and geotechnical practice. The advances have spanned the full spectrum of theory and practice. In addition, unsaturated materials exhibiting complex behaviour such as residual soils, swelling soils, compacted soils, collapsing soils, tropical soils and solid wastes have been integrated in a common understanding of shared behaviour features. It is also noteworthy that unsaturated soil mechanics has proved surprisingly fruitful in expanding to other neighbouring areas such as swelling rocks, rockfill mechanics, and freezing soils. As a consequence, geotechnical engineering involving unsaturated soils can be now approached from a more rational and systematic perspective leading towards an improved and more effective practice. Unsaturated Soils contains the papers presented at the 5th International Conference on Unsaturated Soil (Barcelona, Spain, 6-8 September 2010). They report significant advances in the areas of unsaturated soil behaviour, testing techniques, constitutive and numerical modelling and applications. The areas of application include soil-atmosphere interaction, foundations, slopes, embankments, pavements, geoenviromental problems and emerging topics. They are complemented by three keynote lectures and three general reports covering general issues of modelling, testing and applications. Unsaturated Soils is a comprehensive record of the state-of-the art in unsaturated soil mechanics and a sound basis for further progress in the future. The two volumes will serve as an essential reference for academics, researchers and practitioners interested in unsaturated soils.
Download or read book Introduction to Nuclear Techniques in Agronomy and Plant Biology written by Peter B. Vose and published by Pergamon. This book was released on 1980 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nature of isotopes and radiation; Nuclear reactions; Working with radioisotopes; Detection systems and instrumentation; Radioassay; Radioisotopes and tracer principles; Stable isotopes as tracers; Mainly the use of 15N. Activation analysis for biological samples; X-ray fluorescence spectrography for plants and soils; Autoradiography; Isotopes in soils studies; isotopic tracers in field experimentation; Nuclear techniques in plant science; Nuclear techniques for soil water; Radiation and other induced mutation in plant breeding.
Download or read book Evaluating Soil Moisture and Textural Relationships Using Regression Analysis written by Melvin B. Satterwhite and published by . This book was released on 1980 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
