SURVEYING FOR ENGINEERS

Transcription

1 SURVEYING FOR ENGINEERS

2 Also from The Macmillan Press An Introduction to Engineering Fluid Mechanics, Second Edition J. A. Fox Civil Engineering Materials edited by N. Jackson Reinforced Concrete Design W. H. Mosley and J. H. Bungey Highway Traffic Analysis and Design R. 1. Salter Structural Theory and Analysis 1. D. Todd Engineering Hydrology, Second Edition E. M. Wilson Essential Solid Mechanics, theory, worked examples and problems B. W. Young

3 Surveying for Engineers J. UREN, B.Sc., Ph.D., M.I.H.E. W. F. PRICE, B.Sc., M.Sc., A.R.I.C.S., M.I.H.E. Senior Lecturers, Department of Qvil Engineering, Portsmouth Polytechnic M

4 J. Uren and W. F. Price 1978 Softcover reprint of the hardcover 1st edition All rights reserved. No part of this publication may be reproduced or transmitted, in any form or by any means, without permission. First published 1978 by THE MACMILLAN PRESS LTD London and Basingstoke Associated companies in Delhi Dublin Hong Kong Johannesburg Lagos Melbourne New York Singapore and Tokyo Typeset in 10/11 IBM Press Roman by Reproduction Drawings Ltd. Sutton, Su"ey British library Cataloguing in Publication Data Uren, J Surveying for engineers. 1. Surveying I. Title II. Price, W F 526.9'02'462 TA545 ISBN ISBN (ebook) DOI / This book is sold subject to the standard conditions of the Net Book Agreement. The paperback edition of this book is sold subject to the condition that it shall not, by way of trade or otherwise, be lent, resold, hired out, or otherwise circulated without the publisher's prior consent in any form of binding or cover other than that in which it is published and without a similar condition including this condition being imposed on the subsequent purchaser.

5 Contents Preface Acknowledgements 1. Direct Distance Measurement 1.1 Steel tapes 1.2 Steel taping: fieldwork and corrections 1.3 Steel taping: errors and accuracy 1.4 Steel taping: applications 1.5 Chaining 1.6 Worked example I. 7 Further reading 2. Optical Levels 2.1 The surveying telescope 2.2 The spirit level 2.3 Principle of the level 2.4 The dumpy level 2.5 The tilting level 2.6 The automatic level 2.7 Permanent adjustments of the level 2.8 Further reading 3. Levelling 3.1 Levelling terminology 3.2 Equipment 3.3 Principles of levelling 3.4 Field procedure 3.5 Booking and reduced level calculations 3.6 Accuracy in levelling 3. 7 Errors in levelling 3.8 Summary of the levelling fieldwork 3.9 Additional levelling methods Applications of levelling X xii 1. I I 9 10 II

6 vi CONTENTS 4. Theodolites and their Use Principles of angle measurement The vernier theodolite Modern theodolites Field procedures Adjustments of a theodolite Further reading Traversing Types of traverse Traverse specifications ar.d accuracy Bearings and coordinates Traversing fieldwork: reconnaissance Traversing fieldwork: angular measurement Traversing fieldwork: distance measurement The three-tripod system Traversing calculations Plotting traverse stations Whole-circle bearing and distance calculation from coordinates The National Grid Worked examples Optical Distance Measurement Stadia tacheometry Diagram tacheometers Optical wedge attachments Double-image tacheometers Subtense tacheometry Further reading Electromagnetic Distance Measurement Electromagnetic waves Principle of measurement Modulation Instrument characteristics Atmospheric effects Further EDM corrections Applications of EDM to civil engineering and surveying Further reading Detail surveying Detail Methods Accuracy of detail surveys Chain surveying 144

7 CONTENTS 8.5 Stadia tacheometry I Further tacheometric methods I5I 8. 7 Detail surveying using a theodolite and tape I5I 8.8 Detail surveying using electromagnetic distance measuring equipment I5I 9. Circular Curves I5 3 9.I Types of circular curve I Terminology of circular curves I Radius and degree curves I Length of circular curves I Throughchainage I Design of circular curves I Location of the intersection point and tangent points in the field I Location of the tangent points when the intersection point is inaccessible I Setting out circular curves I60 9.IO Obstructions to setting out I66 9.II Compound circular curves I66 9.I2 Reverse circular curves I67 9.I3 Summary of circular curves I Further reading I68 9.I5 Worked examples I Transition Curves I Radial force and design speed I Superelevation I74 l 0.3 Department of the Environment design tables I76 I0.4 Use of transition curves I79 I 0.5 Length of transition curve to be used I80 I 0.6 Type of transition curve to be used I81 I0.7 The clothoid I82 I0.8 The cubic parabola I Choice of transition curve I87 IO.IO The shift of a cubic parabola I87 I O.II Setting out the composite curve I89 I 0.12 Setting out by coordinates I90 IO.l3 A design method for a composite curve I93 lo.i4 Wholly transitional curves I95 I 0.15 Summary of horizontal curve design 196 I O.I6 Further reading I97 I O.I7 Worked examples I Vertical Curves 202 II.l Gradients 202 1I.2 Purposes of vertical curves Type of curve used 204 vii

8 viii CONTENTS 11.4 Assumptions made in vertical curve calculations 11.5 Equation of the vertical curve 11.6 Sight distances 11.7 K-values 11.8 Use of K-values 11.9 Length of vertical curve to be used Setting out the vertical curve Highest point of a crest, lowest point of a sag Summary of vertical curve design Vertical curves with unequal tangent lengths Computer solution Further reading Worked example 12. Calculation of Areas and Volumes 12.1 Calculation of plan areas 12.2 Calculation of cross-sectional areas 12.3 Calculation of volumes 12.4 Worked example 13. Mass Haul Diagrams 13.1 Formation level and the mass haul diagram 13.2 Drawing the diagram 13.3 Terminology 13.4 Properties of the mass haul curve 13.5 Economics of mass haul diagrams 13.6 Choice of balancing line 13.7 Uses of mass haul diagrams 14. Setting out 14.1 Personnel involved in setting out and construction 14.2 Aims of setting out 14.3 Important considerations 14.4 Stages in setting out 14.5 Preliminaries to setting out 14.6 Methods of horizontal control 14.7 Methods of vertical control 14.8 Positioning techniques 14.9 Setting out a pipeline Setting out a building to ground-floor level 14. I I Transfer of control to ground-floor slab I 4.12 Setting out form work Setting out column positions Controlling verticality in multi-storey structures Transferring height from floor to floor 'i

9 CONTENTS Applications of setting out from coordinates Accuracy of setting out Summary of setting out Further reading Worked examples Index ix

10 Preface Surveying, to the majority of engineers, is the process of measuring lengths, height differences and angles on site either for the preparation of large-scale plans or in order that engineering works can be located in their correct positions on the ground. The correct term for this is engineering surveying and it falls under the general title of land surveying. Since land surveying also includes such topics as photogrammetry (the production of maps and plans from aerial photographs}, hydrographic surveying (the preparation of charts of the sea bed), cadastral surveying (the location of land boundaries for the purposes of ownership and registration), topographic surveying (the production of small-scale maps of large areas showing the major features such as mountains, coastlines and rivers) and geodesy (the study of the shape of the Earth}, the conventional surveying textbooks normally recommended for engineers and engineering students tend to deal with surveying on such a broad front that the really important engineering surveying topics are often not covered adequately. Engineers use land surveying simply as one of the means by which they can undertake their work and there is a defmite limit to the surveying knowledge required by them, beyond which the surveying becomes of interest rather than importance. Specialist land surveyors are usually called in to deal with any unusual problems. The aim of this book, therefore, is to provide a thorough grounding in the basic land surveying techniques required in engineering. Its originality is not so much in the topics which it contains, but more in the emphasis placed on each topic and the depth to which each is covered. Specialised subjects such as photogrammetry and hydrographic surveying are not included for the reasons given above and space is instead given to discussion of the equipment and techniques used in general site work and plan production. The much neglected topic of setting out engineering works (that is, methods other than those used in the setting out of road and railway curves) forms the longest chapter in the book. The full list of topics is given in the contents section but the text splits roughly into two equal p~rts. The initial chapters deal with the equipment commonly used in practice, their methods of use and sources of error, and include details of optical levels, theodolites and distance measuring equipment. The final chapters deal with

11 PREFACE xi methods of producing large-scale plans and the engineering applications of surveying equipment in horizontal and vertical curve construction, earthworks and settingout techniques. Modem equipment is discussed at all times except where the more traditional equipment is ideal for illustrating a particular technique and the use of electronic calculators and computers is discussed wherever applicable. Many worked examples are given, usually at the end of each relevant chapter, to emphasise some of the methods discussed in the text. Systeme International (SI) units are used throughout. A note of caution must be introduced at this point. Although the methods involved in engineering surveying can be studied in textbooks, such is the practical nature of the subject that no amount of reading will turn a student into a competent engineering surveyor. Only by undertaking some practical surveying, under site conditions, and learning how to combine the techniques and equipment as discussed in this text will the student eventually become proficient and produce satisfactory results. Although the book has been written with civil engineering students in mind, it is hoped that it will also be found useful by practising engineers as well as by any other students who undertake engineering surveying as a subsidiary subject. The text covers engineering surveying up to the end of virtually all first-year and most second-year civil engineering degree and diploma courses at universities and polytechnics. Other courses for which it is thought useful are A-level, the ordinary and higher engineering certificates and diplomas and the professional examinations of the various civil engineering related institutions. J. UREN W. F. PRICE

12 Acknowledgements The authors wish to thank all those who contributed in any way to the preparation of this book and, in particular, the following persons and organisations. Mr J. R. Smith and Mr P. F. Gardner, two of our colleagues at Portsmouth Polytechnic, for their considerable help and advice when reading and criticising the original draft and for helping to remove some of the errors. Mrs S. H. Harvey for very kindly typing all the tabular material. The National Swedish Institute for Building Research and, in particular, Dr John van den Berg, for permission to reproduce figures 14.5, 14.14, 14.16, 14.18, 14.30, 14.31, 14.32, 14.33, 14.34, 14.36, 14.37, 14.38, 14.39, 14.40, and Wild Heerbrugg (UK) Ltd for permission to reproduce figures 2. 7, 4.8, 4.11, 4.12, 4.13, 4.16, 4.18, 4.19, 6.5, 6.7, 6.8, 6.9, 6.11 and 7.8. The Construction Industry Research and Information Association for permission to reproduce figures 14.7, 14.11,14.17 and 14.43, which are taken from 'The CIRIA Manual of Setting Out Procedures'. Rank Pullin Controls 'Watts' Surveying Equipment for permission to reproduce figures 2.12, 4.2, 4.4 and 4.6. Figures 1.4 and 1.5 are Crown copyright and are reproduced from BRE Digest 114 by kind permission of the Director, Building Research Establishment. Table 14.1 is reproduced from BRE Digest 202 by courtesy of the Director, Building Research Establishment. Crown copyright, Controller, HMSO. The Department of the Environment for permission to publish tables 10.1 and Tell urometer (UK) Ltd for permission to reproduce figure 7.6. Dr D. H. Wade, Mr G. Coleman, Mr R. Ritson, Mr J. W. Finch and Mr C. Chambers of Portsmouth Polytechnic, for their help with various sections of the text.