■' ~ V- 3 % Vi'.' .AV'A' • \ returned the^o^dein^Redi'^* ! ÙN l,k«ëi TV ' ''â COi •A 'AA'V-' 1164246 (5906424) À ' :/ - V '■ 8g *8 PBx Tt I % ProQuest Number: 10148129 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest ProQuest 10148129 Published by ProQuest LLO (2017). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code Microform Edition © ProQuest LLO. ProQuest LLO. 789 East Eisenhower Parkway P.Q. Box 1346 Ann Arbor, Ml 48106- 1346 Thesis submitted for the degree of PhoD in the Faculty of Engineering of the University of London A THEORY M D DESIGN METHOD FOR CYLINDRICAL SHELL ROOFS AND AN EXPERIMENTAL DETERMINATION OF CERTAIN BASIC DATA PeBe Moriceg B«Scog Battersea PolyteohniOj London 8,W@llg October. 1951o #: AcmoTfimGmmT The author wishes to aoimowledge his indebtedriess to Mr V C Davies^ under #iosG supervision this work was carried out» He also wishes to thank Professor A Gr Pugsley who first suggested the work^^ Mr E H Cooley who assisted in the dieoking of the mathematicsg Mr H E Lewis who helped to take readings during experiments and Messrs F L Wilson and A G Mossg who made most of the apparatus = % O/ 7 LIST OF CONTENTS PART I « INTRODUCTION AND THEORY Pag© Chapter 1 Introduction 1 - - 8 2 A review of shell theory 9 «*> BS 3 Elasticity theory 24 37 4 General shell equations 38 58 5 The membrane condition of cylindrical shells 59 68 6 The edge disturbance equation 69 85 7 Edge beams 86 98 8 The general solution 99 105 PART II ^ DESIGN Chapter 1 Factors affecting design 1 - 4 2 Design methods 5 ^ 8 3 Design examples 9 « 56 PART III » EXPERIMENTAL STUDIES Chapter 1 Concrete 1 12 2 Apparatus 13 23 5 Poisson*s ratio tests 24 »=■ 34 4 Edge beam torsion 35 48 LIST OF COHTMTS continued PART IV - APPEND I0B8 . Page Chapter 1 References pp 2 2 Notation pp 8 3 Bibliography pp 33 4 A note on the plotting ofp rojeotories of principle stress pp 7 5 List of expressions required in developing the edge disturbance equation pp 3 6 Solution of the equation (x^ )^4* 4 “ 0 pp S PART I Introduction and Theory CHAPTER 1 Introductd.on The inherent strength of a curved structure when loaded normally is evinced by the use of shells in nature as a protective covering to certain eggs, nuts^ insects, etc. It is therefore not surprising that structural shells should be used extensively in civil engineering constructions It was not possible' to make full use of shells until comparatively recently because early building materials possessed little or no tensile strength, The complications involved are well demonstrated by the use of flying buttresses in G-othi.c cathedrals to provide an arch thrust to the vaulted roof. The advent of wrought iron and later steel had little influence since these materials when used in an economi cally thin membrane are well within the range of buckling for normal roof sizes and loadingSo It was not, therefore, until the advent of reinforced concrete, a comparatively cheap bulk material capable of resist ing both tensile and compressive stress, that the full advantage of shell structures could be used. In its most generally used form, and that with which this work is concerned, the shell consists of a thin membrane curved in one direction only, forming a segment of a right cylinder which is supported at its ends and not along its edges, (Figure 1), m,.n)i##&ri### Figure ^, It is evident that in the direction of a generator the shell is spanning as a beam and therefore the lower portions of the shell will be in tension. In small spans the tensile stresses induced are small, and sufficient steel can be introduced into the membrane itself without much thickening. (Figure 2)« DUCT --‘No.3/24'0'‘BAYS Figure 2. /