K.A. Zalka
Taylor & Francis | 0415234832 | 2000 | PDF | 360 pages | 6 Mb
DESCRIPTION
The global structural analysis of buildings can be carried out following two routes. First, sophisticated and complex computer packages based on the finite element method can handle even huge structures with a great number of elements. Second, analytical methods can also deal with whole structures leading to simple closed-form solutions, with the additional benefit of providing fast checking facilities for the computer based methods. This book follows the latter route. As well as describing and solving the complex theoretical problems of bracing systems with real-world examples, the author presents simple procedures and closed-form formulae which make it possible for the practising structural engineer to carry out a general structural analysis of the bracing system of building structures in minutes. Global Structural Analysis of Buildings is a practical reference for professional civil and structural engineers in construction firms, consultancies and building research organisations. The theoretical aspects of the book will appeal to postgraduates, lecturers and researchers of structural analysis and design.
LIST OF CONTENT
1 Introduction 1
1.1 Background 1
1.2 General assumptions 3
1.3 The structure of the book 4
2 Spatial behaviour 7
2.1 Basic principles 7
2.2 The equivalent column and its characteristics 8
2.3 The spatial behaviour of the equivalent column 16
3 Stability and frequency analyses 18
3.1 Stability analysis 19
3.1.1 Doubly symmetrical systems—basic critical loads 20
3.1.2 Coupling of the basic modes; combined swaytorsional buckling 26
3.1.3 Concentrated top load; single-storey buildings 32
3.1.4 Shear mode situations 33
3.1.5 Soil-structure interaction 36
3.1.6 Individual beam-columns 41
3.2 Frequency analysis 43
3.2.1 Doubly symmetrical systems—basic natural frequencies 44
3.2.2 Coupling of the basic modes; combined lateraltorsional vibrations 52
3.2.3 Concentrated mass at top level; single-storey buildings 55
3.2.4 Soil-structure interaction 57
3.2.5 Supplementary remarks 60
4 Stress analysis: an elementary approach 63
4.1 Horizontal load 64
4.1.1 Wind 64
4.1.2 Seismic load 65
4.1.3 Construction misalignment 67
4.1.4 Comparisons 68
4.2 Buildings braced by parallel walls 69
4.2.1 Basic principles 70
4.2.2 Load distribution 72
4.2.3 Deformations 75
4.3 Buildings braced by perpendicular walls 76
4.3.1 Load distribution 77
4.3.2 Deformations 81
4.4 Buildings braced by frameworks 82
4.4.1 Frameworks in a symmetrical arrangement 82
4.4.2 Frameworks in an asymmetrical arrangement 83
4.5 Maximum bending moments in the bracing elements 86
4.6 Worked examples 90
4.6.1 Example 1: building braced by parallel walls 90
4.6.2 Example 2: building braced by perpendicular walls 91
4.6.3 Comparison 94
4.6.4 Example 3: building braced by frameworks and a single wall 94
4.7 Discussion 96
5 Stress analysis: an advanced approach 98
5.1 The equivalent column and its load 99
5.2 Deformations of the equivalent column 103
5.2.1 Horizontal displacements 103
5.2.2 Rotations 105
5.3 Deformations of the building 108
5.4 Load distribution among the bracing elements 110
5.4.1 Shear forces and bending moments 110
5.4.2 Torsional moments 121
5.5 Stresses in the bracing elements 126
5.6 Concentrated force at top level; single-storey buildings 129
5.7 Buildings with Ixy=0, subjected to uniformly distributed horizontal load 137
5.8 Worked example: a 6-storey building in London 139
5.8.1 Model: individual shear walls 140
5.8.2 Model: built-up shear walls and cores 144
5.9 Supplementary remarks 149
5.9.1 Frameworks and coupled shear walls 149
5.9.2 Bracing systems with shear or a mixture of shear and bending deformations 150
5.9.3 Special cases—scope for simplification 150
5.9.4 Second-order effects 151
5.9.5 Soil-structure interaction 152
6 Illustrative example; Qualitative and quantitative evaluation 154
6.1 Case 1 155
6.1.1 Critical load 157
6.1.2 Fundamental frequency 159
6.1.3 Maximum stresses and deformations 160
6.2 Case 2 163
6.2.1 Critical load 165
6.2.2 Fundamental frequency 166
6.2.3 Maximum stresses and deformations 167
6.3 Case 3 169
6.3.1 Critical load 171
6.3.2 Fundamental frequency 171
6.3.3 Maximum stresses and deformations 172
6.4 Evaluation 174
7 Global critical load ratio 176
7.1 Global critical load ratio—Global safety factor 177
7.2 Global critical load ratio—Performance indicator 178
7.3 Further applications 181
8 Use of frequency measurements for the global analysis 182
8.1 Stiffnesses 183
8.2 Critical loads 184
8.2.1 Multistorey buildings under uniformly distributed floor load 184
8.2.2 Concentrated top load; single-storey buildings 186
8.3 Deformations 186
8.3.1 Multistorey buildings subjected to horizontal load of trapezoidal distribution 187
8.3.2 Concentrated force at top level; single-storey buildings 189
8.3.3 Deformations of the building 191
9 Equivalent wall for frameworks; Buckling analysis of planar structures 192
9.1 Introduction 192
9.2 Characteristic deformations, stiffnesses and part critical loads 194
9.3 Frameworks on fixed supports 199
9.3.1 The application of summation theorems 200
9.3.2 The continuum model 201
9.3.3 The sandwich model 204
9.3.4 Design formulae 208
9.4 Frameworks on pinned supports 210
9.4.1 Frameworks without ground floor beams 212
9.4.2 Frameworks with ground floor beams 213
9.5 Frameworks with ground floor columns of different height 214
9.6 Analysis of coupled shear walls by the frame model 216
9.7 Frameworks with cross-bracing 218
9.7.1 Shear stiffness and shear critical load 220
9.7.2 Critical loads 224
9.7.3 Structures with global regularity 225
9.8 Infilled frameworks 226
9.9 Equivalent wall for 3-dimensional analysis 228
9.10 Shear walls 230
9.11 Symmetrical cross-wall system buildings 231
9.12 Planar bracing elements: a comparison 233
9.13 Supplementary remarks 236
10 Test results and accuracy analysis 238
10.1 Description of the models 238
10.2 Horizontal load on Model ‘M1’ 241
10.3 Horizontal load on Model ‘M2’ 243
10.4 Comparative analysis of the formulae for horizontal load 245
10.5 Dynamic tests 246
10.6 Stability tests 248
10.6.1 Model ‘M1’ 250
10.6.2 Model ‘M2’ 251
10.6.3 Deformation of the bracing elements 252
11 Evaluation; design guidelines 254
11.1 Spatial behaviour 255
11.2 Stability analysis 255
11.3 Frequency analysis 256
11.4 Stresses and deformations 258
11.5 Structural performance of the bracing system 259
11.6 Stability of planar structures 260
11.6.1 Low-rise to medium-rise (4–25-storey) structures 260
11.6.2 Tall (over 25-storey) structures 263
11.6.3 Structural performance of planar bracing elements 263
AppendixA Cross-sectional characteristics for bracing elements 266
Appendix B The generalized power series method for eigenvalue problems 278
Appendix C Mode coupling parameter κ 283
References 315
Further reading 325
Name index 331
Subject index 335
EDITORIAL REVIEW
Taylor & Francis | 0415234832 | 2000 | PDF | 360 pages | 6 Mb
DESCRIPTION
The global structural analysis of buildings can be carried out following two routes. First, sophisticated and complex computer packages based on the finite element method can handle even huge structures with a great number of elements. Second, analytical methods can also deal with whole structures leading to simple closed-form solutions, with the additional benefit of providing fast checking facilities for the computer based methods. This book follows the latter route. As well as describing and solving the complex theoretical problems of bracing systems with real-world examples, the author presents simple procedures and closed-form formulae which make it possible for the practising structural engineer to carry out a general structural analysis of the bracing system of building structures in minutes. Global Structural Analysis of Buildings is a practical reference for professional civil and structural engineers in construction firms, consultancies and building research organisations. The theoretical aspects of the book will appeal to postgraduates, lecturers and researchers of structural analysis and design.
LIST OF CONTENT
1 Introduction 1
1.1 Background 1
1.2 General assumptions 3
1.3 The structure of the book 4
2 Spatial behaviour 7
2.1 Basic principles 7
2.2 The equivalent column and its characteristics 8
2.3 The spatial behaviour of the equivalent column 16
3 Stability and frequency analyses 18
3.1 Stability analysis 19
3.1.1 Doubly symmetrical systems—basic critical loads 20
3.1.2 Coupling of the basic modes; combined swaytorsional buckling 26
3.1.3 Concentrated top load; single-storey buildings 32
3.1.4 Shear mode situations 33
3.1.5 Soil-structure interaction 36
3.1.6 Individual beam-columns 41
3.2 Frequency analysis 43
3.2.1 Doubly symmetrical systems—basic natural frequencies 44
3.2.2 Coupling of the basic modes; combined lateraltorsional vibrations 52
3.2.3 Concentrated mass at top level; single-storey buildings 55
3.2.4 Soil-structure interaction 57
3.2.5 Supplementary remarks 60
4 Stress analysis: an elementary approach 63
4.1 Horizontal load 64
4.1.1 Wind 64
4.1.2 Seismic load 65
4.1.3 Construction misalignment 67
4.1.4 Comparisons 68
4.2 Buildings braced by parallel walls 69
4.2.1 Basic principles 70
4.2.2 Load distribution 72
4.2.3 Deformations 75
4.3 Buildings braced by perpendicular walls 76
4.3.1 Load distribution 77
4.3.2 Deformations 81
4.4 Buildings braced by frameworks 82
4.4.1 Frameworks in a symmetrical arrangement 82
4.4.2 Frameworks in an asymmetrical arrangement 83
4.5 Maximum bending moments in the bracing elements 86
4.6 Worked examples 90
4.6.1 Example 1: building braced by parallel walls 90
4.6.2 Example 2: building braced by perpendicular walls 91
4.6.3 Comparison 94
4.6.4 Example 3: building braced by frameworks and a single wall 94
4.7 Discussion 96
5 Stress analysis: an advanced approach 98
5.1 The equivalent column and its load 99
5.2 Deformations of the equivalent column 103
5.2.1 Horizontal displacements 103
5.2.2 Rotations 105
5.3 Deformations of the building 108
5.4 Load distribution among the bracing elements 110
5.4.1 Shear forces and bending moments 110
5.4.2 Torsional moments 121
5.5 Stresses in the bracing elements 126
5.6 Concentrated force at top level; single-storey buildings 129
5.7 Buildings with Ixy=0, subjected to uniformly distributed horizontal load 137
5.8 Worked example: a 6-storey building in London 139
5.8.1 Model: individual shear walls 140
5.8.2 Model: built-up shear walls and cores 144
5.9 Supplementary remarks 149
5.9.1 Frameworks and coupled shear walls 149
5.9.2 Bracing systems with shear or a mixture of shear and bending deformations 150
5.9.3 Special cases—scope for simplification 150
5.9.4 Second-order effects 151
5.9.5 Soil-structure interaction 152
6 Illustrative example; Qualitative and quantitative evaluation 154
6.1 Case 1 155
6.1.1 Critical load 157
6.1.2 Fundamental frequency 159
6.1.3 Maximum stresses and deformations 160
6.2 Case 2 163
6.2.1 Critical load 165
6.2.2 Fundamental frequency 166
6.2.3 Maximum stresses and deformations 167
6.3 Case 3 169
6.3.1 Critical load 171
6.3.2 Fundamental frequency 171
6.3.3 Maximum stresses and deformations 172
6.4 Evaluation 174
7 Global critical load ratio 176
7.1 Global critical load ratio—Global safety factor 177
7.2 Global critical load ratio—Performance indicator 178
7.3 Further applications 181
8 Use of frequency measurements for the global analysis 182
8.1 Stiffnesses 183
8.2 Critical loads 184
8.2.1 Multistorey buildings under uniformly distributed floor load 184
8.2.2 Concentrated top load; single-storey buildings 186
8.3 Deformations 186
8.3.1 Multistorey buildings subjected to horizontal load of trapezoidal distribution 187
8.3.2 Concentrated force at top level; single-storey buildings 189
8.3.3 Deformations of the building 191
9 Equivalent wall for frameworks; Buckling analysis of planar structures 192
9.1 Introduction 192
9.2 Characteristic deformations, stiffnesses and part critical loads 194
9.3 Frameworks on fixed supports 199
9.3.1 The application of summation theorems 200
9.3.2 The continuum model 201
9.3.3 The sandwich model 204
9.3.4 Design formulae 208
9.4 Frameworks on pinned supports 210
9.4.1 Frameworks without ground floor beams 212
9.4.2 Frameworks with ground floor beams 213
9.5 Frameworks with ground floor columns of different height 214
9.6 Analysis of coupled shear walls by the frame model 216
9.7 Frameworks with cross-bracing 218
9.7.1 Shear stiffness and shear critical load 220
9.7.2 Critical loads 224
9.7.3 Structures with global regularity 225
9.8 Infilled frameworks 226
9.9 Equivalent wall for 3-dimensional analysis 228
9.10 Shear walls 230
9.11 Symmetrical cross-wall system buildings 231
9.12 Planar bracing elements: a comparison 233
9.13 Supplementary remarks 236
10 Test results and accuracy analysis 238
10.1 Description of the models 238
10.2 Horizontal load on Model ‘M1’ 241
10.3 Horizontal load on Model ‘M2’ 243
10.4 Comparative analysis of the formulae for horizontal load 245
10.5 Dynamic tests 246
10.6 Stability tests 248
10.6.1 Model ‘M1’ 250
10.6.2 Model ‘M2’ 251
10.6.3 Deformation of the bracing elements 252
11 Evaluation; design guidelines 254
11.1 Spatial behaviour 255
11.2 Stability analysis 255
11.3 Frequency analysis 256
11.4 Stresses and deformations 258
11.5 Structural performance of the bracing system 259
11.6 Stability of planar structures 260
11.6.1 Low-rise to medium-rise (4–25-storey) structures 260
11.6.2 Tall (over 25-storey) structures 263
11.6.3 Structural performance of planar bracing elements 263
AppendixA Cross-sectional characteristics for bracing elements 266
Appendix B The generalized power series method for eigenvalue problems 278
Appendix C Mode coupling parameter κ 283
References 315
Further reading 325
Name index 331
Subject index 335
EDITORIAL REVIEW
