Download or read book A Constitutive Model for Fiber reinforced Soils written by Cheng-Wei Chen and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fiber inclusion to improve the properties of compacted soil is becoming increasingly common in geotechnical engineering projects. However, the technique requires extensive testing on soil and fiber samples before it can be implemented. Although research performed over the last few decades has evaluated certain fiber-reinforced soil properties and formations, the development of constitutive models for fiber-reinforced soil has lagged. This dissertation aims to minimize testing requirements for fiber-reinforced specimens and thereby to encourage the implementation of fiber-reinforced soils in engineering. Extensive testing on unreinforced and reinforced silty and Ottawa sand specimens was performed to develop and to validate a constitutive model for predicting the stress strain-volume-pore pressure response of fiber-reinforced soils. Results showed that the effective friction angle and cohesion intercept increased significantly in consolidated undrained CU) and consolidated-drained (CD) triaxial compression tests for both fiber-reinforced silty sand and Ottawa sand. The shear strength parameters of fiber-reinforced silty sand and Ottawa sand are strain dependent so more shear strain was needed to mobilize fiber resistance for specimens consolidated at higher effective stresses. Moreover, the laboratory results suggested that fiber-reinforcement provides both a deviatoric (q[function]) and a hydrostatic (p[function]) contribution to the stresses in the specimens. However, the hydrostatic contribution of fibers varied according to different soil types and loading conditions. The proposed constitutive model to predict the mechanical properties of fiber-reinforced soils is based on superposition of the response of unreinforced soil and the response due to fibers. Key assumptions in the model include: (1) fibers are uniformly distributed in the specimens. (2) [integral] mob accounts for the reductions in fiber strain due to relative slip between the fibers and the soil, and varies with effective consolidation stress, soil types, and loading conditions, (3) yielding is considered, (4) shear distortion ([for all] is equal to triaxial shear strain ([for all]q), (5) the total axial strain in the fibers ([for all] t) is equal to 0.25 times axial strain plus 1.68 times volumetric strain from tests on unreinforced specimens, and (6) the initial p[function] 0 and q[function] 0 are used to account for the compaction, extrusion, and consolidation process. The model was found to be capable of reproducing the deviatoric stress well for all reinforced silty sand and Ottawa sand. The predicted pore pressure and volumetric strain were all in a close agreement with the observed behavior up to large strains for both soils. However, the predicted volumetric strain behavior shows some tendency to over-predict the dilatancy of the reinforced silty sand specimens consolidated less than 20-psi (140-[kappa]Pa). The predictions in fiber deviatoric and hydrostatic stresses in CU tests matched reasonably well and followed the same trends as the measured behavior, except for specimens consolidated at higher effective stresses. In CD tests, the deviatoric and hydrostatic stresses matched reasonably well and mimicked the measured behavior, but tended to deviate slightly from the observed response at large strains.

Download or read book Development of a Constitutive Model for Fiber reinforced Soils written by Ricardo J. Romero and published by . This book was released on 2003 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the research was to develop a model to predict the effective stress-strain-pore pressure-volume change behavior of fiber-reinforced soils from the superposition of the response of unreinforced soil and the response attributed to fibers. Consolidated-undrained triaxial compression tests (CU tests) and consolidated-drained triaxial compression tests (CD tests) were performed on comparable fiber-reinforced and unreinforced soil specimens. The results of these tests indicate that the inclusion of fibers significantly improves the strength of soils, and increases the peak strength as well as the strain to failure. Fiber-reinforcement increased both the cohesion intercept ( c ' ) and the effective stress friction angle ([straight phi] ' ). It was found that c ' and [straight phi] ' are strain dependent. Reinforced specimens sheared under undrained conditions exhibited higher pore pressure than unreinforced specimens. Under drained conditions, reinforced specimens showed significantly less dilation than unreinforced specimens, which is in agreement with the response observed in undrained tests. It was postulated that these responses are caused by an "internal confining stress" provided by the fibers. Based on the results of laboratory tests, a model is proposed to predict the stress-strain-pore pressure-volume change behavior of fiber-reinforced soils. The key components of the model include mechanism to account for initial stresses in the fibers induced during compaction, saturation, and consolidation; stresses induced during shearing of the specimens; stresses due to volume changes in the specimen; and, finally, pullout or yielding of the fibers. The proposed model is capable of reproducing very well the stress-strain behavior. Pore pressures and volume changes are well predicted at shear strains less than 10 percent and under consolidation pressures less than 550 kPa. However, pore pressures and volume changes are not well predicted at larger strains.

Download or read book An Incremental Constitutive Model for Geofiber Reinforced Soil written by Kexin Ma and published by . This book was released on 2004 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geofiber reinforced soil (GFRS) is highly inhomogeneous with its two constituents: geofiber and soil. The overall behaviors of GFRS are determined by its characteristics such as the properties of constituents, geometry of geofiber, content and distribution of geofibers in the reinforced soil, and their interactions. Because the macroscopic approach alone is unable to respond to the effect of local characteristics, a micromechanical approach is desirable for the analysis of GFRS. In this dissertation, an incremental constitutive model considering microscopic damage was developed in which applied mean-field theory is used in each steps of the analysis. The roles of soil and geofiber in the reinforced soil, the interface between the geofiber and the soil, and the fiber-matrix interaction were analyzed for both local and global responses. An interface evolutionary law was introduced into the model and was used with each step to obtain the total stiffness of GFRS, which is a function of micro-structural parameters and the applied macro strain. A series of torsional shear tests were conducted to provide data on the properties of the soil and to verify the validity and accuracy of the proposed model. Three types of samples, classified in terms of the weight of their geofiber contents of 0.0%, 0.2% and 0.5%, were investigated in these tests. They were also subjected to a variety of loading frequencies ranging from 0.01 Hz to 5.0Hz. The shear modulus of soil as a function of shear strain amplitude and loading frequency was obtained by using curve-fitting techniques in the analysis of test results. Results from the torsional shear tests indicate that the presence of geofiber leads to higher stiffnesses of the reinforced soil and the higher geofiber content is more effective than the lower fiber content. It also indicates that the shear stress increases in a nonlinear manner with an increase in shear strain. Nonlinear behavior is more pronounced in reinforced soil than that in unreinforced soil. The shear modulus always increases with an increase in loading frequency in this test range. When comparing the results determined by the experiments and those determined by theoretical predictions, good agreement was found regarding the torsional shear behaviors of GFRS. -- Abstract.

Download or read book Fundamentals of Fibre Reinforced Soil Engineering written by Sanjay Kumar Shukla and published by Springer. This book was released on 2017-01-16 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended to serve as a one-stop reference on fibre-reinforced soils. Over the past 30-35 years, the engineering behaviour of randomly distributed/oriented fibre-reinforced soil, also called simply fibre-reinforced soil, has been investigated in detail by researchers and engineers worldwide. Waste fibres (plastic waste fibres, old tyre fibres, etc.) create disposal and environmental problems. Utilization of such fibres in construction can help resolve these concerns. Research studies and some field applications have shown that the fibres can be utilized in large quantities in geotechnical and civil engineering applications in a cost-effective and environmentally friendly manner. This book covers a complete description of fibres, their effects when included within a soil or other similar materials such as the fly ash, and their field applications. It gives a detailed view of fibre-reinforced soil engineering. The book will be useful to students, professional, and researchers alike, and can also serve as a text for graduate coursework and professional development programs

Download or read book Geosynthetics in Civil and Environmental Engineering written by Guang-xin Li and published by Springer Science & Business Media. This book was released on 2009-03-07 with total page 875 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geosynthetics in Civil and Environmental Engineering presents contributions from the 4th Asian Regional Conference on Geosynthetics held in Shanghai, China. The book covers a broad range of topics, such as: fundamental principles and properties of geosynthetics, testing and standards, reinforcement, soil improvement and ground improvement, filter and drainage, landfill engineering, geosystem, transport, geosynthetics-pile support system and geocell, hydraulic application, and ecological techniques. Special case studies as well as selected government-sponsored projects such as the Three Gorges Dam, Qinghai-Tibet Railway, and Changi Land reclamation project are also discussed. The book will be an invaluable reference in this field.

Download or read book Endochronic Constitutive Modeling of Marine Fiber Reinforced Concrete and Frozen Soil written by Raja K. Gopal and published by . This book was released on 1985 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Constitutive Modeling of Soils and Rocks written by Pierre-Yves Hicher and published by John Wiley & Sons. This book was released on 2013-03-01 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title provides a comprehensive overview of elastoplasticity relating to soil and rocks. Following a general outline of the models of behavior and their internal structure, each chapter develops a different area of this subject relating to the author's particular expertise. The first half of the book concentrates on the elastoplasticity of soft soils and rocks, while the second half examines that of hard soils and rocks.

Download or read book Vibrations of Soils and Foundations written by Frank Edwin Richart and published by Prentice Hall. This book was released on 1970 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: For graduate students in soil dynamics with a background in statics and elementary dynamics.

Download or read book A New Method for Numerical Analysis of Reinforced Soil written by Yu-xin Jie and published by . This book was released on 2012 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are two general approaches to the analysis of reinforced soil. One is to deal with the soil and the reinforcement separately, assuming that they interact with each other through friction on the interface between them. The other is to consider the reinforced soil as an anisotropic homogeneous composite, such that the forces of interaction between soil and reinforcement material become internal, something that does not appear in calculations of the stress and deformation of the composite. In this paper, a new method is proposed for the analysis of reinforced soil. The basic principle of this method is that only the soil skeleton is taken into account, while the reinforcing effect is considered as an equivalent additional stress acting on the soil skeleton in the direction of the reinforcement bedding. The existing constitutive model for soil can be directly used in this method without having to formulate new models. The procedures involved in the determination of the equivalent additional stress and other relevant parameters are also presented in the paper. Examples show that the new method can reasonably describe the stress-strain relationship of fiber-reinforced soil and soil structures reinforced with layers of reinforcement.

Download or read book Design oriented Constitutive Model for Steel Fiber Reinforced Concrete written by Felipe Laranjeira de Oliveira and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Modeling of Soil Constitutive Relationship written by Qingyang Ren and published by Springer Nature. This book was released on 2021-09-01 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book adopts numerical method to model soil constitutive relationship while it abandons the traditional idea of looking for plastic potential as the only way to model. Firstly, the triaxial compression tests of expansive soil, sand and clay under different stress paths are introduced; then the elastoplastic constitutive equations of expansive soil, sand and clay under various stress paths are established by numerical modeling method; finally, the constitutive equations are embedded in the finite element program and verified by comparing the finite element calculation results of the triaxial test soil samples with the corresponding test results. The modeling obtains high accuracy.

Download or read book Proceedings of GeoShanghai 2018 International Conference Fundamentals of Soil Behaviours written by Annan Zhou and published by Springer. This book was released on 2018-05-10 with total page 1026 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the second volume of the proceedings of the 4th GeoShanghai International Conference that was held on May 27 - 30, 2018. The book, entitled “Fundamentals of Soil Behaviours”, presents the recent advances and technology in the understanding and modelling of fundamentals of soil’s behaviours. The subject of this book covers a wide range of topics related to soil behaviours in geotechnical engineering, geoenvironmental engineering and transportation engineering. The state-of-the-art theories, methodologies and findings in the related topics are included. This book may benefit researchers and scientists from the academic fields of soil and rock mechanics, geotechnical engineering, geoenvironmental engineering, transportation engineering, geology, mining and energy, as well as practical engineers from industry. Each of the papers included in this book received at least two positive peer reviews. The editors would like to express their sincerest appreciation to all of the anonymous reviewers all over the world, for their diligent work.

Download or read book Finding Solutions of the 21st Century Transportation Problems Through Research and Innovations written by Zahid Hossain and published by Springer Nature. This book was released on 2021-07-14 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents challenges in transportation infrastructures and geotechniques, advancements in recycling, soil stabilization and reinforcement technologies, and assessments of roadway conditions using modern tools and techniques. The articles presented in this volume focus on fundamental investigations on various aspects of civil engineering materials and structures. The scope of this volume is the application of findings for solving problems in geotechnical, pavement, concrete and transportation engineering using through smart, green and emerging techniques. The primary audience of this work will be researchers, professionals, and practitioners around the world. This volume is based on contributions to the 6th GeoChina International Conference on Civil & Transportation Infrastructures: From Engineering to Smart & Green Life Cycle Solutions -- Nanchang, China, 2021.

Download or read book New Horizons in Earth Reinforcement written by Jun Otani and published by CRC Press. This book was released on 2023-05-31 with total page 1809 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earth reinforcement techniques are used worldwide, providing dependable solutions to a wide range of geotechnical engineering problems.Well-established earth reinforcement technologies are regularly augmented by new materials, innovative construction techniques and advances in design and analysis. Furthermore, reinforced earth structures are increasingly seen as expedient and economical techniques in disaster situations, such as earthquakes, flooding or tsunamis. NEW HORIZONS in EARTH REINFORCEMENT contains contributions from the 5th International Symposium on Earth Reinforcement, Kyushu, Japan, 14-16 November 2007, and presents the very latest earth reinforcement techniques and design procedures. The volume showcases advances in materials and emerging applications, with special emphasis on disaster mitigation and geoenvironmental issues. The book will be invaluable to academics and professionals in geotechnical engineering.

Download or read book Constitutive Modelling of Soils and Fibre reinforced Soils written by Thomas Bower and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Transactions of the American Society of Civil Engineers written by American Society of Civil Engineers and published by . This book was released on 2005 with total page 1176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. 29-30 contain papers of the International Engineering Congress, Chicago, 1893; v. 54, pts. A-F, papers of the International Engineering Congress, St. Louis, 1904.

Download or read book Constitutive Modeling and Flexural Analysis of Steel Fiber Reinforced Concrete for Structural Applications written by Cha-Don Lee and published by . This book was released on 1990 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: