Download or read book Interpretation of Load Transfer Mechanism for Piles in Unsaturated Expansive Soils written by Yunlong Liu and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Water infiltration associated with natural precipitation events or other artificial activities such as pipe leaks in expansive soils significantly influence the engineering properties; namely, coefficient of permeability, shear strength and volume change behavior. For this reason, it is challenging to design or construct geotechnical infrastructure within or with expansive soils. Several billions of dollars losses, world-wide, can be attributed to the repairing, redesigning and retrofitting of infrastructure constructed with or within expansive soils, annually. Piles are widely used as foundations in expansive soils extending conventional design procedures based on the principles of saturated soil mechanics. However, the behavior of piles in unsaturated expansive soils is significantly different from conventional non-expansive saturated soils. Three significant changes arise as water infiltrates into expansive soil around the pile. Firstly, soil volume expansion contributes to ground heave in vertical direction. Secondly, volume expansion restriction leads to development of the lateral swelling pressure resulting in an increment in the lateral earth pressure in the horizontal direction. Thirdly, pile-soil interface shear strength properties change due to variations in water content (matric suction) of the surrounding soil. These three changes are closely related to matric suction variations that arise during the water infiltration process. For this reason, a rational methodology is necessary for the pile load transfer mechanism analysis based on the mechanics of unsaturated soils. Studies presented in this thesis are directed towards developing simple methods to predict the load transfer mechanism changes of piles in expansive soils upon infiltration. More emphasis is directed towards the prediction of the pile mechanical behavior which includes the pile head load-displacement relationship, the pile axial force (shaft friction) distribution and the pile base resistance using unsaturated mechanical as a tool. The function of matric suction as an independent stress state variable on the mechanical behavior pile is highlighted. More specifically, following studies were conducted: (i) Previous studies on various factors influencing the load transfer mechanisms of piles in unsaturated expansive soils are summarized and discussed to give a background of current research. More specifically, state-of-the-art reviews are summarized on the application of piles in expansive soils, mobilization of lateral swelling pressure, mobilization of unsaturated pile-soil interface shear strength and methods available for the load transfer analysis of piles in expansive soils. (ii) Employing unsaturated soil mechanics as a tool, theoretical methods are proposed for estimating the lateral earth pressure variations considering the mobilization of lateral swelling pressure. The proposed methods are verified using two large-scale laboratory studies and two field studies from published literatures. (iii) The shear displacement method and load transfer curve methods used traditionally for pile load transfer mechanisms analysis for saturated soils were modified to extend their applications for unsaturated expansive soils. The influence of volume change characteristics and unsaturated soil properties on unsaturated expansive soils are considered in these methods. The validation of the modified shear displacement method and modified load transfer curve method were established using a large-scale model test performed in the geotechnical engineering lab of University of Ottawa and a field case study results from the published literature. (iv) A large-scale model pile infiltration test conducted in a typical expansive soil from Regina in Canada in the geotechnical lab of University of Ottawa is presented and interpreted using the experimental data of volumetric water content suction measurements and shear strength data. The results of the comprehensive experiment studies are also used to validate the proposed modified shear displacement method and modified load transfer curve method achieving reasonable good comparisons. The proposed modified shear displacement method and modified load transfer curve method are simple and require limited number soil properties including the soil water characteristic curve (SWCC), matric suction profile upon wetting and drying and some soil physical properties. Due to these advantages, they can be easily and conveniently applied in engineering practice for prediction of the mechanical behavior of piles in unsaturated expansive soils, which facilitate practicing engineers to produce sound design of pile foundation in unsaturated expansive soils in a simplistic manner.
Download or read book Load Transfer Mechanisms for Piles in Soft Soils written by Andrew L. Palmer and published by . This book was released on 1994 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pile Load Tests to Evaluate Load Transfer Mechanisms written by MW. Montgomery and published by . This book was released on 1979 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Load transfer mechanisms in 17 test piles are evaluated by means of an extensive monitoring program during full-scale load testing and are compared with behavior computed by a displacement compatibility analysis. H-piles, Raymond step taper piles, auger-cast piles, and steel pipe piles were tested, in many cases to failure. These piles were installed at a power generating station in saprolites of the Piedmont Province of Georgia. Deflection was measured at the butt of each pile and at the tip and one or two intermediate levels in most piles by means of telltales. A boring and laboratory testing program was an integral part of the program. Load transfer mechanisms are evaluated by means of a displacement compatibility analysis using results of the field and laboratory investigations. Good agreement between computed pile behavior and that determined by the monitoring program during load testing is demonstrated. The results of the monitoring program and the enhanced understanding of the load transfer mechanisms involved make a comparison of the effectiveness of the various pile types possible and allow development of rational installation criteria.
Download or read book Single Piles and Pile Groups Under Lateral Loading written by Lymon C Reese and published by CRC Press. This book was released on 2000-01-01 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Guiding the professional through the complexities of lateral-load design, this book and CD-ROM combination introduces the procedures involved in piles and pile group design. This is a problem that can only be solved by accounting for the soil resistance as related to the lateral deflection of the pile. Intricate equations are derived and fully explained, enabling the designer to find the critical loads, either causing a pile to be overloaded or causing too much lateral deflection. The CD-ROM contains simplified versions of two required programs that allow the reader to check the solutions of some of the examples given in the book and to find answers to related problems.
Download or read book Load Transfer Criteria for Numerical Analysis of Axially Loaded Piles in Sand Part 1 Load Transfer Criteria written by R. L. Mosher and published by . This book was released on 1984 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part I describes a study of load-transfer criteria for analysis of axially loaded piles in sand using the discrete springs soil model. Various analysis methods for axially loaded piles are presented, along with a literature review of pile behavior in sands focusing on the changes the soil undergoes during pile installation. Available criteria for spring representation of soil are presented and summarized. The criteria are compated with actual field data from pile load tests and are critically evaluated based on these comparisons. Because of the poor performance of the available criteria, new criteria are proposed. The new criteria use maximum side and tip resistance values presented by Castello (1980). Castello's values are modified by the author to reflect the field data from the Lower Mississippi Valley. Displacement functions for side and tip resistance are developed based on correlations with field data for pile load tests. The new criteria are evaluated against pile load test data. Use of the critieria is demonstrated in an outline of an analysis. The new criteria are used to develop a set of design curves for the practicing engineer. Part II of this report is published under a separate cover, and presents load capacity curves for select steel and concrete pile.
Download or read book Parametric Studies of Load Transfer Mechanism of Piles Embedded in Homogeneous Soil written by Chitta Ranjan Saha and published by . This book was released on 1999 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Best Of The Blues Project written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pile Design and Construction Rules of Thumb written by Ruwan Abey Rajapakse and published by Butterworth-Heinemann. This book was released on 2016-02-20 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pile Design and Construction Rules of Thumb presents Geotechnical and Civil Engineers a comprehensive coverage of Pile Foundation related theory and practice. Based on the author’s experience as a PE, the book brings concise theory and extensive calculations, examples and case studies that can be easily applied by professional in their day-to-day challenges. In its first part, the book covers the fundamentals of Pile Selection: Soil investigation, condition, pile types and how to choose them. In the second part it addresses the Design of Pile Foundations, including different types of soils, pile groups, pile settlement and pile design in rock. Next, the most extensive part covers Design Strategies and contains chapters on loading analysis, load distribution, negative skin friction, design for expansive soils, wave equation analysis, batter piles, seismic analysis and the use of softwares for design aid. The fourth part covers Construction Methods including hammers, Inspection, cost estimation, load tests, offshore piling, beams and caps. In this new and updated edition the author has incorporated new pile designs such as helical, composite, wind turbine monopiles, and spiral coil energy piles. All calculations have been updated to most current materials characteristics and designs available in the market. Also, new chapters on negative skin friction, pile driving, and pile load testing have been added. Practicing Geotechnical, and Civil Engineers will find in this book an excellent handbook for frequent consult, benefiting from the clear and direct calculations, examples, and cases. Civil Engineering preparing for PE exams may benefit from the extensive coverage of the subject. Convenient for day-to-day consults Numerous design examples for sandy soils, clay soils, and seismic loadings Now including helical, composite, wind turbine monopiles, and spiral coil energy piles Methodologies and case studies for different pile types Serves as PE exam preparation material
Download or read book Load transfer Criteria for Numerical Analysis of Axially Loaded Piles in Sand written by Reed L. Mosher and published by . This book was released on 1982 with total page 742 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study on Load Transfer of Model Friction Piles written by Richard Milton Franke and published by . This book was released on 1969 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Previous investigations concerned with disturbance of soft clay by driving displacement piles are summarized. The initiation of excess pore water pressures due to pile driving, and mechanisms of load transfer are also described, along with the applicapability of model pile testing in analysis of the various phenomena. Load tests were conducted on assorted sizes of model friction piles embedded in sedimented soil samples with consisted of a silt and clay mixture. Pilot holes of various diameters were cut in the samples. A theoretical load distribution curve was used to calculate the load transferred to the soil as a function of pile embedment. Laboratory vane shear test results were compared to the load transferred to the soil by the pile. Results of the research program indicate that: 1) The ratio of the load transferred to the soil to the undrained strength of the soil changes with depth in the sample, and with the ratio of the pilot hole diameter to the pile diameter, 2) an optimum pilot hole size exists for each pile which offers a balance between low soil disturbance and high load carrying capacity, 3) the soil sample size should be four to five times the pile size to achieve valid load test results, and 4) the ultimate load that a friction pile can support increases with time after pile insertion and with increased rates of penetration"--Abstract, leaf ii.
Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Construction on Axial Load Transfer Along Bored Piles in Residual Soils written by Jin Yu and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Enhanced Load Transfer Analysis for Friction Piles Using a Modified Borehole Shear Test written by Sherif S. AbdelSalam and published by . This book was released on 2012 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study discusses the development and use of a modified borehole shear test (mBST) to improve the prediction of the load-displacement and load-distribution responses for axially loaded friction piles in cohesive soils using the load-transfer analysis method (i.e., t-z analysis). Unlike available approaches that rely on empirical or semi-empirical correlations to generate the shear stress displacement at the soil-pile interface (i.e., t-z curves), the mBST enables direct field measurement of the t-z curves at the soil-pile interface. As part of this study, three full-scale vertical static load tests (SLTs) were conducted on instrumented steel H piles. The t-z analysis was carried out utilizing the TZPILE software with measured t-z curves via the mBST (i.e., the TZ-mBST model). When comparing results of the analysis with the measured responses for the three test piles, it was found that: (1) the TZ-mBST provides proper prediction for the initial part of the measured load-displacement response from SLT results, with a difference not exceeding 10 %; (2) the TZ-mBST analysis provides acceptable prediction of the pile capacity; (3) the TZ-mBST analysis matches the load distribution along the pile length with a maximum difference of 8.3 %; and (4) the analysis with directly measured t-z curves using the mBST provide improved predictions of the pile response when compared to the empirical CPT-based analysis.
Download or read book Design of Pile Foundations written by Aleksandar Sedmak Vesić and published by Transportation Research Board. This book was released on 1977-01-01 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Mechanics and Foundations written by Muniram Budhu and published by John Wiley and Sons. This book was released on 2010-12-21 with total page 788 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discover the principles that support the practice! With its simplicity in presentation, this text makes the difficult concepts of soil mechanics and foundations much easier to understand. The author explains basic concepts and fundamental principles in the context of basic mechanics, physics, and mathematics. From Practical Situations and Essential Points to Practical Examples, this text is packed with helpful hints and examples that make the material crystal clear.
