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Elasticity, shrinkage,
creep and thermal

movement

7.1 Learning objectives

The main learning objectives of this chapter are to explain and describe the following
features appertaining to concrete:
• Principal causes and factors affecting elastic, creep, shrinkage and thermal movements
• Typical ranges of strain occurring in practice
• Mechanisms of shrinkage and creep
• Measurement of shrinkage and creep
• Effects of movements on concrete in service
• Practical prediction of movements

7.2 Introduction

Although the elastic and thermal deformation behaviour of concrete have been known for
some time, it is only relatively recently that the importance of creep and drying shrinkage
have been recognized. It was probably at the beginning of the twentieth century when
Hatt (1907) first reported increased, non-elastic deflections of reinforced concrete beams

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