How Structures Work

Preface x 1 Brackets and Bridges 1 Cooper's tragedy 2 The Forth Bridge 4 Members in compression 6 The Quebec Bridge 8 Forces in a bracket 9 The design process 13 Stresses 14 2 Stiffening a Beam - Girder Bridges 16 The simple truss 22 Tension trusses 27 Girder bridges: The Forth Bridge 31 3 Arches and Suspension Bridges 33 Building an arch 35 Blackfriars Bridge 37 Pontypridd Bridge 39 The forces in an arch 39 Practical issues 41 Forces within the arch ring 43 Edwards's failure 48 An unexpected failure 49 Arch with point load 50 Iron and concrete arches 51 The suspension bridge 54 Arches in buildings: Flying buttresses 57 Arches in walls 60 4 Bringing the Loads to the Ground - The Structural Scheme 63 Introduction 63 The alternatives 64 Nature of the loads 66 Choices 68 'Flow of forces' or action and reaction 71 Describing the structure 73 Structures are three?]dimensional 75 Statically indeterminate structures 76 5 Safe as Houses? - Walls 79 Bricks and mortar 81 Point loads and openings 85 Cavity walls 88 Thick walls 90 Foundation loads 93 Horizontal loads 94 Rafter thrusts 98 Foundation stresses 101 6 Frames - A Problem of Stability 103 Timber framing 104 Construction of a barn 108 Bracing forces 111 Bending in the post 112 Light frame construction 113 The coming of iron 115 The frame today 122 The multistorey frame 126 Columns 130 7 Floors and Beams - Deflections and Bending Moments 134 The need for science 140 Floors and deflections 140 The forces in the beam 142 Strain 143 Galileo's cantilever 145 Finding the stresses 147 From cantilever to beam 148 Iron and steel beams 150 Cast iron 150 Reinforced concrete beams 153 Continuous beams 155 Shear 159 Two?-way floors 160 Other structures in bending 163 Prestressing 168 8 Providing Shelter - Roofs 173 Common rafter roofs 174 Purlin roofs 179 Longitudinal stability 185 The roof truss 188 The coming of iron 190 Three?-dimensional roofs 192 9 Structures in a Three?-Dimensional World 198 Vaults 198 The pointed vault 202 Elaborations on the basic vault form 203 Building vaults 206 Domes 207 Some historical examples 212 The modern three?-dimensional structure 216 Anticlastic forms 220 Structures in tension 222 Structures for their time and place 224 10 Materials and Workmanship 226 Walling materials 227 Timber 228 Iron and steel 229 Compatibility of materials 233 Material development and design 234 Appendix: Some Elements of Grammar 235 Glossary 241 Index 250