GEOTECHNICAL ENGINEERING THIS PAGE IS BLANK Copyright © 2006, 1995, 1993 New Age International (P) Ltd., Publishers Published by New Age International (P) Ltd., Publishers All rights reserved. No part of this ebook may be reproduced in any form, by photostat, microfilm, xerography, or any other means, or incorporated into any information retrieval system, electronic or mechanical, without the written permission of the publisher. All inquiries should be emailed to [email protected] ISBN (10) : 81-224-2338-8 ISBN (13) : 978-81-224-2338-9 PUBLISHING FOR ONE WORLD NEW AGE INTERNATIONAL (P) LIMITED, PUBLISHERS 4835/24, Ansari Road, Daryaganj, New Delhi - 110002 Visit us at www.newagepublishers.com Dedicated to the memory of My Parenu-in-l_ Smt. Ramalakshmi & Dr. A. Venkat& Subba Bao for ,1Mb-'-and o/Yeetio,.lo".. and aU 1M meMbue ofm y (Gmjly. THIS PAGE IS BLANK THE 1'Hnm PREFACE TO EDITION With the enthusiastic response to the Second Edition of "GEOTECHNICAL ENGINEERING" from the academic community. the author has undertaken the task of preparing the Third Edition. The important features of this Edition are minor revision/additions in Chapters 7. 8, 10, 17 and 18 and change over of the Illustrative Examples and Praclice Problems originally left in the MKS units into the S.I. units so that the book is completely in the S.I. units. This is because the so-caned "Period of Transition" may be considered to have been over. The topics involving minor revision/addition in the respective chapters specificaUy are : Chapter 7 Estimation of the settlement due to secondary compression. Chapter 8 Uses and appli.cations of Skempton'g pore pressure parameters, and "Stress-path" approach and its usefulness. Chapter 10 Unifonn load on an annular area (Ring foundation). Chapter 17 Reinforced Earth and Geosynthetics, and their applications in geotechnical practice. Chapter 18 The art of preparing a soil investigation report. Only brief and elementary treatment of the above has been given. Consequential changes at the appropriate places in the text, contents, answers to nu merical problems, section numbers, figure numbers, chapter-wise references, and the indices have also been made. A few printing errors noticed in the previous edition have been rectified. The reader is requested to refer to the latest revised versions of the 1.8. Codes mentioned in the book. In view of all these, it is hoped that the bouk would prove even more useful to the stu dents than the previous edition. The author wishes to thank the geotechnical enbrineenng fraternity for the excellent support given to his book. Finally, the author thanks the Publishers for bringing out this Edition in a relatively short time, while impro.ving the quality of production. C. Venkatramaiah Tirupati India Vii THIS PAGE IS BLANK THE EnmON PREFACE TO FIRST The author does not intend to be apologetic for adding yet another book to the existing list in the field of Geotechnical Engineering. For onc thing, the number of books avaiiable cannot be considered too large, although certain excellent reference books by Stalwarts in the field are available. For another, the number of books by Indian Authors is only a few. Specifically speak. ing, the number of books in this field in the S.I. System of Units is small, and books from Indian authors are virtually negligible. This fact, coupled with the author's observation that not many books are available designed specifically to meet the requirements of undergraduate curncu lum in Civil Engineering and Technology, has been the motivation to undertake this venture. The special features of this book are as follows: 1. The S.L System of Units is adopted along with the equivalents in the M.K.S. Units in some instances. (A note on the S.l. Units commonly used in Geotechnical Engineer ing is included). 2. Reference is made to the relevant Indian Standards·, wherever applicable, and ex tracts from these are quoted for the benefit of the student as well a8 the practising engineer. 3. A 'few illustrative problems and problems for practice are given in the M.K.S. Units to facilitate those who continue to use these Units during the transition period. 4. The number of illustrative problems is fairly large compared to that in other books. This aspect would be helpful to the student to appreciate the various types of prob lems likely to be encountered. 5. The number of problems for practice at the end of each chapter is also fairly large. The answers to the numerical Froblems are given at the end of the book. 6. The illustrative examples and problems are graded carefully with regard to the toughness. 7. A few objective questions are also included at the end. This feature would be useful to students even during their preparation for competitive and other examinations such as GATE. B. "Summary of Main Points", given at the end of each Chapter, would be vcr)' helpful to a student trying to brush up his preparatiun on the eve of the examination. 9. Chapter-wise references are given; this is CODl,!idered a better way to encourage fur ther reading than a big Bibliography at the end . • Note: References are invited to the latest editions ofthesc specifications for further details. These standards are available from Indian Standards Institution, New Delhi and it.s Regional Branch and In epection Offices at Ahmedabad, Bangalorc. Bhopal. llhubaneshwar. Bombay, Calcutta. Chandigarh, Hyderabad, Jaipur. Kanpur, Madras, Patnn. Pune and Trivilndrum. ix