Microcomputer Applications in Structural Engineering
W. H. Mosley Department of Civil Engineering
University of Liverpool and
Nanyang Technological Institute Singapore
W. J. Spencer Department of Civil Engineering Chisholm Institute of Technology
Caulfield East Victoria, Australia
M MACMILLAN PRESS
LONDON
Contents
Preface xiii
1 An Introduction to Microcomputers \
1.1 Introduction 1 1.2 The Microcomputer System 2
1.2.1 The Microprocessor 3 1.2.2 Computer Memory 3
1.3 Program and Variable Storage in a Microcomputer 7 1.3.1 Off-line Storage 7
1.4 Programming the Microcomputer 8 1.4.1 Machine-code programming 9 1.4.2 The Use of a Monitor 15
1.5 Selecting a Microcomputer 17 Further Reading 19
2 BASIC Programming on a Microcomputer 20
2.1 The Elements of Programming in BASIC 22 2.1.1 A BASIC Program 22 2.1.2 An Introduction to the Operating System 23
2.2 Variables, Operators and the Assignment Statement 24 2.2.1 Numeric Variables and Numeric Constants 25 2.2.2 Integer Variables 25 2.2.3 String Variables and String Constants 25 2.2.4 Operators 26 2.2.5 The Assignment Statement 26
2.3 Input and Output of Data 27 2.3.1 READ-DATA Statements 27 2.3.2 The INPUT Statement 27 2.3.3 The PRINT Statement 28
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2.4 Control Statements 29 2.4.1 The GOTO and ON GOTO Statements 29 2.4.2 The IF Statement 29 2.4.3 FOR-NEXTloops 30 2.4.4 Subroutines and the GOSUB, RETURN Statements 31
2.5 Functions 33 2.5.1 Arithmetic and Trigonometric Functions 33 2.5.2 String Functions 33 2.5.3 User-defined Functions 34
2.6 Arrays and Advanced Features 35 2.6.1 Subscripted Variables and the DIMension Statement 35 2.6.2 Application Examples using Subscripted Variables 36
2.7 Programming Concepts 40 2.7.1 Principles of Programming 41 2.7.2 Editing, Checking and Debugging Programs 42 2.7.3 Elements of Modular Programming 44 2.7.4 Improving Storage Efficiency and Speed 50 2.7.5 Other Features of BASIC 52
Further Reading 54
3 Organisation of a Personal Computer System 55
3.1 File Concepts and File Storage 56 3.1.1 File Types 56 3.1.2 Disk Operating Systems and Initialising Disks 57 3.1.3 Data Files 58
3.2 Further File-handling Commands 63 3.3 The Use of Files on a Microcomputer System 65 3.4 Documentation of Programs 69
3.4.1 Program Documentation 69 3.4.2 Using the Microcomputer to Store the Documentation 71
3.5 Maintaining a Personal Computer System 75 3.5.1 Backing-up Files 75 3.5.2 Test Routines and Memory Checks 76 3.5.3 Using a Log Book 77
3.6 Extended Use of a Microcomputer System 77 3.6.1 Alternative Operating Systems 78 3.6.2 Input/Output Peripherals 79
Further Reading 79
4 Simple Programming Applications in Analysis and Design SO
4.1 Program for the Analysis of a Single Span Beam 80 4.1.1 Listing of the Beam Analysis Program 86 4.1.2 Application Example of the Beam Analysis Program 88
CONTENTS ix
4.2 Program for Stiffness and Carry-over Factors for a Member of Variable Cross-section 89 4.2.1 Listing of the Stiffness and Carry-over Factor Program 92 4.2.2 Application Example of the Stiffness and Carry-over Program 94
4.3 Program for General Section Properties Calculation 95 4.3.1 Listing of the Section Properties Program 97 4.3.2 Application Example of the Section Properties Program 99
4.4 Program for the Solution of Simultaneous Equations 100 4.4.1 Listing of the Simultaneous Equations Program 102 4.4.2 Application Example of the Simultaneous Equations Program 102
4.5 Program for the Analysis of a Pile Group 103 4.5.1 Listing of the Pile Group Analysis Program 105 4.5.2 Application Example of the Pile Group Analysis Program 107
Further Reading 108
5 Programs for Structural Analysis 109
5.1 Details of the Stiffness Method 111 5.2 Analysis of a Plane Frame 112
5.2.1 Stages of the Plane Frame Program 113 5.2.2 Sign Convention for the Plane Frame Program 120 5.2.3 Listing of the Plane Frame Program and its Variables 120 5.2.4 Details of an Example using the Plane Frame Program 129 5.2.5 Further Development of the Plane Frame Program 131
5.3 Analysis of a Grillage 132 5.3.1 Modifying the Plane Frame Program to Form the
Grillage Program 134 5.3.2 Listing of the Revised Lines for the Grillage Program 135 5.3.3 Details of an Example Using the Grillage Program 136
5.4 Members of Variable Cross-section 138 Further Reading 141
6 Programs for Steelwork Design 142
6.1 Steel Column Design 142 6.1.1 Flow Diagram for the Design of a Steel Column 144 6.1.2 Stages of the Steel Column Design Program 146 6.1.3 Additional Options of the Steel Column Design Program 152 6.1.4 Listing of the Steel Column Design Program and its Variables 153 6.1.5 Details of Examples Using the Steel Column Design Program 158
6.2 Steel Beam Design 160 6.2.1 Flow Diagram for the Design of a Steel Beam 162 6.2.2 Stages of the Steel Beam Design Program 164 6.2.3 Listing of the Steel Beam Design Program and its Variables 167 6.2.4 Details of an Example Using the Steel Beam Design Program 172
Further Reading 174
X CONTENTS
7 Programs for Reinforced Concrete Design 175
7.1 Analysis of the Structure 176 7.1.1 Flow Diagram for the Analysis of a Substitute Frame 179 7.1.2 Details of the Stages of the Substitute Frame Analysis
Program 181 7.1.3 Further Development of the Substitute Frame Analysis
Program 187 7.1.4 Listing of the Substitute Frame Analysis Program and
its Variables 188 7.1.5 Details of an Example Using the Substitute Frame Program 195
7.2 Reinforced Concrete Beam Design 199 7.2.1 Design of Bending Reinforcement for a Rectangular Beam
Section 200 7.2.2 Design of Reinforcement for a Flanged Beam Section 205 7.2.3 Listing of the R.C. Beam Design Program and its Variables 208
7.3 Selection of Bar Sizes 211 7.3.1 Listing of the Bar Selection Program 211
7.4 Reinforced Concrete Column Design 212 7.5 Symmetrical Arrangement of Column Reinforcement 213
7.5.1 Flow Diagram for the Design of a Column with a Symmetrical Arrangement of Reinforcement 215
7.5.2 Details of the Stages of the Column Design with Symmetrical Reinforcement Program 216
7.5.3 Listing of the Program to Design a Column with Symmetrical Reinforcement and its Variables 217
7.6 Unsymmetrical Arrangement of Column Reinforcement 220 7.6.1 Listing of the Program to Design a Column with
Unsymmetrical Reinforcement 221 Further Reading 222
8 Graphics on the Microcomputer 223
8.1 The Graphics Screen 224 8.2 The Visual Display Unit 225 8.3 Line Generation on a Graphics Screen 225
8.3.1 The Graphics Mode 227 8.3.2 Color Selection 227 8.3.3 The Line-drawing Command 228
8.4 The Graphics Software 228 8.4.1 Fundamental Operations in Graphics 229 8.4.2 Drawing a Two-dimensional Object—an Example of
Graphics Software 231 8.4.3 Text plus Graphics 235
CONTENTS XI
8.5 Peripheral Devices Used with Graphics 236 8.5.1 Hard Copy Units and Printers 236 8.5.2 Plotting Units 237 8.5.3 Graphics Tablets and Digitisers 237 8.5.4 Other Input Devices 239
8.6 Organisation of Computer Graphics 239 8.7 Examples of Computer Graphics Programs 241
8.7.1 A General Graph-plotting Program 241 8.7.2 Drawing a Bending Moment Diagram 247
8.8 Computer Graphics Systems 248 Further Reading 248
Appendix: Decimal, Hexadecimal and Binary Number Systems 249
Index 256
