Concrete structures must be designed not only to be safe against failure but also to perform satisfactorily in use. This book is written for practising engineers and students, and focuses on design methods for checking deflections and cracking which can affect the serviceability of reinforced and prestressed concrete structures. The authors present accurate and easy-to-apply methods of analysing immediate and long-term stresses and deformations. These methods allow designers to account for variations of concrete properties from project to project and from country to country, making the book universally applicable. Comprehensively updated, this third edition of Concrete Structures also includes four new chapters covering such topics as: non-linear analysis of plane frames, design for serviceability of prestressed concrete, serviceability of members reinforced with fibre polymer bars, and the analysis of time-dependent internal forces with linear computer programs that are routinely used by structural designers. A website accompanies the book, featuring three design calculation programs related to stresses in cracked sections, creep coefficients and time-dependent analysis.
The book contains numerous examples, some of which are worked out in the SI units and others in the Imperial units. The input data and the main results are given in both SI and Imperial units. The book is not tied to any specific code, although the latest American and European codes of practice are covered in the appendices.
Table of Contents
Preface to the third edition. Acknowledgements. Note. The SI system of units and British equivalents. Notation. 1. Creep and shrinkage of concrete and relaxation of steel. 1.1 Introduction. 1.2 Creep of Concrete. 1.3 Shrinkage of Concrete. 1.4 Relaxation of prestressed steel. 1.5 Reduced relaxation. 1.6 Creep superposition. 1.1 The aging coefficient ?: definition. 1.8 Equation for the aging coefficient ?. 1.9 Relaxation of concrete. 1.10 Step-by Step calculation of the relaxation function for concrete. 1.11 Age-adjusted elasticity modulus. 1.12 General. 2 Stress and strain of uncracked sections. 2.1 Introduction. 2.2 Sign convention. 2.3 Strain, stress and curvature in composite and homogeneous cross-sections. 2.4 Strain and stress due to non-linear temperature variation. 2.5 Time-dependent stress and strain in a composite section. 2.6 Summary of analysis of time-dependent strain and stress. 2.7 Examples worked out in British units. 2.8 General. 3 Special cases of uncracked sections and calculation of displacements. 3.1 Introduction. 3.2 Prestress loss in a section with one layer of reinforcement. 3.3 Effects of presence of non-prestressed steel. 3.4 Reinforced concrete section without prestress: effects of creep and shrinkage. 3.5 Approximate equations for axial strain and curvature due to creep. 3.6 Graphs for rectangular sections. 3.7 Multi-stage prestressing. 3.8 Calculation of displacements. 3.9 Example worked out in British units. 3.10 General. 4 Time-dependent internal forces in uncracked structures: analysis by the force method. 4.1 Introduction. 4.2 The force method. 4.3 Analysis of time-dependent changes of internal forces by the force method. 4.4 Movement of supports of continuous structures. 4.5 Accounting for the reinforcement. 4.6 Step-by-step analysis by the force method. 4.7 Example worked out in British units. 4.8 General. 5 Time-dependent internal forces in uncracked structures: analysis by the displacement method. 5.1 Introduction. 5.2 The displacement method. 5.3 Time-dependent changes in fixed-end forces in a homogeneous member. 5.4 Analysis of time-dependent changes in internal forces in continuous structures. 5.5 Continuous composite structures. 5.6 Time-dependent changes in the fixed-end forces in a composite member. 5.7 Artificial restraining forces. 5.8 Step-by-step analysis by the displacement method. 5.9 General. 6 Analysis of time-dependent internal forces with conventional computer programs. 6.1 Introduction. 6.2 Assumptions and limitations. 6.3 Problem statement. 6.4 Computer programs. 6.5 Two computer runs. 6.6 Equivalent temperature parameters. 6.7 Multi-stage loading. 6.8 Examples. 6.9 General. 7 Stress and strain of cracked sections. 7.1 Introduction. 7.2 Basic assumptions. 7.3 Sign convention. 7.4 Instantaneous stress and strain. 7.5 Effects of creep and shrinkage on a reinforced concrete section without prestress. 7.6 Partial prestressed sections. 7.7 Flow chart. 7.8 Example worked out in British units. 7.9 General.8 Displacements of cracked members. 8.1 Introduction. 8.2 Basic assumptions. 8.3 Strain due to axial tension. 8.4 Curvature due to bending. 8.5 Curvature due to a bending moment combined with an axial force. 8.6 Summary and idealized model for calculation of deformations of cracked members subjected to N and/or M. 8.7 Time-dependent deformations of cracked members. 8.8 Shear deformations. 8.9 Angle of twist due to torsion. 8.10 Examples worked out in British units. 8.11 General. 9 Simplified prediction of deflections. 9.1 Introduction. 9.2 Curvature coefficients, k. 9.3 Deflection prediction by interpolation between uncracked and cracked states. 9.4 Interpolation procedure: the 'bilinear method'. 9.5 Effective moment of inertia. 9.6 Simplified procedure for calculation of curvature at a section subjected to M and N. 9.7 Deflections by bilinear method: members subjected to M and N. 9.8 Estimation of probable defection: method of 'global coefficients'. 9.9 Deflection of two-way s