Aluminium Design and Construction John Dwight

More documents

Recommendations

Info

Acknowledgements I am indebted to the following people who have provided unstinting help: Michael Bayley, British Alcan; Dr P.S.Bulson CBE, former head of MEXE; Ron Cobden, aluminium designer, formerly with British Alcan; Professor S.L.Harris, formerly of Lancaster University; Dr G.H.Little, Birmingham University; Richard Mahoney and David Keevil, Aluminium Federation; Professor C.D.Marsh, Concordia University, Montreal, who has been designing in aluminium for 50 years and still is; Dr O.T.Midling, Hydro Aluminium, Norway; Dr N.S.Moss and Dr J.Powell, CIBA; Professor D.A.Nethercot, Nottingham University; Dr M.H.Ogle, TWI; Dr Ian Robertson, Cegelec (Alstom), France; Morris de Rohan, Agent General for South Australia, London; Professor F.Soetens, TNO Bouw, Delft; Wayne Thomas, TWI; Philip Tindall, Hyder Consulting; Professor N.S.Trahair, University of Sydney; Don Webber, MEXE; Dr Roy Woodward, formerly with Aluminium Laboratories, Banbury. I would also like to thank Marica de Lopez and Susan Bennett who have done a noble job in typing the text. Finally, I reserve extra special thanks for my wife Jo, who has cheerfully put up with aluminium pervading the house for far too long. Copyright 1999 by Taylor & Francis Group. All Rights Reserved.
List of symbols The following symbols appear generally thoughout the book. Others are defined as they arise. A area of section Ae area of effective section Aw area of weld deposit Az area of nominal heat-affected zone (HAZ) D overall depth of section E modulus of elasticity G shear modulus H warping factor I second moment of area (‘inertia’) Ip polar inertia Iuu , Ivv principal inertias Ixx (Iyy ) inertia about centroidal axis xx (yy) Ixy product of inertia ℑ St Venant torsion factor L unsupported member length for overall buckling M moment arising under factored loading Mc calculated moment resistance M – moment arising per unit length of weld under factored loading M – c calculated moment resistance per unit length of weld N fatigue endurance (cycles to failure) P axial force arising under factored loading Pc calculated axial force resistance P – force arising under factored loading, per fastener or per unit length of weld P – c calculated force resistance, per fastener or per unit length of weld R – reaction force between plates per bolt (friction-grip bolting) S plastic section modulus (uniaxial moment) Sm plastic section modulus (biaxial moment) Sp reduced plastic modulus in presence of axial load (uniaxial moment) Copyright 1999 by Taylor & Francis Group. All Rights Reserved.
Page 1 and 2: Aluminium Design and Construction C
Page 3 and 4: First published 1999 by E & FN Spon
Page 5 and 6: 2.2.1 Rolling mill practice 2.2.2 P
Page 7 and 8: 5 Limit state design and limiting s
Page 9 and 10: 8.2.6 Use of interpolation for semi
Page 11 and 12: 10.3.2 Inertias for a section with
Page 13: Preface Aluminium is easily the sec
Page 17 and 18: uu, vv principal axes w effective s
Page 19 and 20: 1.1.3 The industrial metal It is on
Page 21 and 22: where A is the section area (mm 2 )
Page 23 and 24: 1.3.1. The good points about alumin
Page 25 and 26: Deflection Because of the lower mod
Page 27 and 28: 1.4.4 Establishment of the alloys I
Page 29 and 30: 1.5.2 New technology Most of alumin
Page 31 and 32: large span, where self-weight is a
Page 33 and 34: These tend to be in all-aluminium c
Page 35 and 36: Close-up of the M-dec system, which
Page 37 and 38: Aluminium glazing system for commer
Page 39 and 40: Nat West Media Centre, Lords Cricke
Page 41 and 42: The main requirements for the produ
Page 43 and 44: in which t and w are in mm. These a
Page 45 and 46: Figure 2.1 Extrusion process (direc
Page 47 and 48: Figure 2.2 Typical extrusion die. t
Page 49 and 50: Figure 2.6 ‘Semi-hollow’ profil
Page 51 and 52: especially the stronger alloys in t
Page 53 and 54: Figure 2.9 Conventional profiles. 2
Page 55 and 56: 2.4 TUBES By tubes we mean hollow s
Page 57 and 58: CHAPTER 3 Fabrication 3.1 PREPARATI
Page 59 and 60: Figure 3.1 Alternative designs for
Page 61 and 62: Figure 3.2 Thread insert. a coil-sp
Page 63 and 64: 3.3 ARC WELDING 3.3.1 Use of arc we
Page 65 and 66:
adjusted. The technique is claimed
Page 67 and 68:
For welds of minimum or fatigue qua
Page 69 and 70:
Figure 3.5 Friction-stir welding: s
Page 71 and 72:
are, and the designer/fabricator mu
Page 73 and 74:
cartridge, and mixing takes place a
Page 75 and 76:
3.7.4 Painting Alloys having durabi
Page 77 and 78:
Where a range is given, as for the
Page 79 and 80:
will be only slightly above that fo
Page 81 and 82:
heating the metal to a temperature
Page 83 and 84:
Table 4.4 Characteristics of differ
Page 85 and 86:
softening in the heat-affected zone
Page 87 and 88:
60 alloys, are: BSEN.485 plate and
Page 89 and 90:
Firure 4.3 Nominal composition and
Page 91 and 92:
popular alloys in the series are: 6
Page 93 and 94:
Figure 4.6 Variation of tensile str
Page 95 and 96:
undercarriages of aircraft. They ar
Page 97 and 98:
Figure 4.11 Minimum stress-strain c
Page 99 and 100:
AC.51400 This is another non-heat-t
Page 101 and 102:
times that of the actual pits) prod
Page 103 and 104:
The severity of bimetallic corrosio
Page 105 and 106:
Nominal loading. Nominal loads are
Page 107 and 108:
2. Material factor (� m ). In the
Page 109 and 110:
design does not, because stress at
Page 111 and 112:
Table 5.2 Summary of limiting stres
Page 113 and 114:
Figure 5.4 Plastic strain at workin
Page 115 and 116:
example, a reduced value might be t
Page 117 and 118:
The parameter � depends purely on
Page 119 and 120:
CHAPTER 6 Heat-affected zone soften
Page 121 and 122:
area of softening. With 7xxx-type m
Page 123 and 124:
Figure 6.3 Typical hardness plots a
Page 125 and 126:
6.4 SEVERITY OF HAZ SOFTENING 6.4.1
Page 127 and 128:
Figure 6.6 Categories of welded joi
Page 129 and 130:
Figure 6.10 One-inch rule, extent o
Page 131 and 132:
e allowed for in design by replacin
Page 133 and 134:
Figure 6.13 Predicted area (A z ) o
Page 135 and 136:
Figure 6.15 Overlapping HAZs. nomin
Page 137 and 138:
In determining A zp , an appropriat
Page 139 and 140:
failure plane in the HAZ, close to
Page 141 and 142:
With MIG welding, an electrode-posi
Page 143 and 144:
CHAPTER 7 Plate elements in compres
Page 145 and 146:
(a) Compression member elements The
Page 147 and 148:
Table 7.1 Classification of element
Page 149 and 150:
Figure 7.4 Slender internal element
Page 151 and 152:
Figure 7.7 shows curves of � ° p
Page 153 and 154:
(7.9a) (7.9b) The strain gradient c
Page 155 and 156:
(through the centroid) for ß S . F
Page 157 and 158:
Figure 7.13 Outstands under strain-
Page 159 and 160:
Figure 7.15 Reinforced elements. Th
Page 161 and 162:
Figure 7.18 Stiffener location for
Page 163 and 164:
Figure 7.20 Slender reinforced inte
Page 165 and 166:
CHAPTER 8 Beams 8.1 GENERAL APPROAC
Page 167 and 168:
8.2.2 Section classification The di
Page 169 and 170:
that for the gross section. It woul
Page 171 and 172:
the usual manner. Line 1 in the fig
Page 173 and 174:
1. Fully compact sections. The limi
Page 175 and 176:
Figure 8.8 Transverse and longitudi
Page 177 and 178:
8.3.4 Shear resistance of bars and
Page 179 and 180:
Figure 8.12 Tension-field action. i
Page 181 and 182:
Figure 8.14 Moment/shear interactio
Page 183 and 184:
depending on the estimated degree o
Page 185 and 186:
where a is the stiffener spacing an
Page 187 and 188:
plates (if fitted), p v =limiting m
Page 189 and 190:
ending moment diagram. Two cases ar
Page 191 and 192:
Figure 8.23 Sections covered in Tab
Page 193 and 194:
where: I yy , I vv =inertia about m
Page 195 and 196:
post (Section 8.6.4) or by some oth
Page 197 and 198:
Figure 8.26 Components of deflectio
Page 199 and 200:
9.1.2 Classification of the cross-s
Page 201 and 202:
hole. Alternatively, it might fail
Page 203 and 204:
Figure 9.2 Limiting stress p b for
Page 205 and 206:
The determination of l involves a c
Page 207 and 208:
Figure 9.6 Monosymmetric section. I
Page 209 and 210:
Figure 9.9 Limiting stress p b for
Page 211 and 212:
where s=� s /� t s =slenderness
Page 213 and 214:
Figure 9.11 Type-R sections covered
Page 215 and 216:
Figure 9.14 Four standardized profi
Page 217 and 218:
9.7.2 Secondary bending in trusses
Page 219 and 220:
Table 9.5 Necessary checks for memb
Page 221 and 222:
Figure 9.18 Axial load with biaxial
Page 223 and 224:
1. Tension members. The localized f
Page 225 and 226:
Figure 10.1 Symmetric plastic bendi
Page 227 and 228:
We now turn to monosymmetric sectio
Page 229 and 230:
distance of its centroid from the n
Page 231 and 232:
Figure 10.6 Elements of sections. I
Page 233 and 234:
10.3.3 Product of inertia The produ
Page 235 and 236:
Usually the conditions are such as
Page 237 and 238:
Table 10.2 Torsion constant. Factor
Page 239 and 240:
Figure 10.12 Warping. Conventional
Page 241 and 242:
where b, t=element width and thickn
Page 243 and 244:
10.5.3 Evaluation of warping When t
Page 245 and 246:
For sections where the position of
Page 247 and 248:
(10.31) where: e=distance that S li
Page 249 and 250:
10.5.9 Asymmetric sections Before s
Page 251 and 252:
CHAPTER 11 Joints This chapter cons
Page 253 and 254:
the use of limiting stresses taken
Page 255 and 256:
and the summation is made for all t
Page 257 and 258:
Figure 11.3 Interaction diagram for
Page 259 and 260:
k in order to give a fair compariso
Page 261 and 262:
3. The design is satisfactory if fo
Page 263 and 264:
When the method of surface preparat
Page 265 and 266:
11.3.3 Weld force arising In many c
Page 267 and 268:
Table 11.6 Limiting stress p w (N/m
Page 269 and 270:
where p a =limiting stress for unwe
Page 271 and 272:
Figure 11.11 Interaction diagram fo
Page 273 and 274:
Manufacturers of structural adhesiv
Page 275 and 276:
11.4.6 Creep Shear strength figures
Page 277 and 278:
Figure 11.15 Effect of glue-line th
Page 279 and 280:
Table 11.7 and Figure 11.17 provide
Page 281 and 282:
11.4.11 Resistance calculations for
Page 283 and 284:
high value reflects the various unc
Page 285 and 286:
therefore usually presented in term
Page 287 and 288:
For example: The loading spectrum i
Page 289 and 290:
act on the structure. However, BS.8
Page 291 and 292:
Figure 12.4 Crack propagation: (a)
Page 293 and 294:
12.5 CLASSIFICATION OF DETAILS 12.5
Page 295 and 296:
i.e. a joint extending in the same
Page 297 and 298:
when the design life is low or when
Page 299 and 300:
Methods (2) and (3) are difficult t
Page 301:
it reverts to line 1. The slope s o
show all

Aluminium Design and Construction John Dwight

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?