ABSTRACT

In the previous chapter, simplified methods were presented for the determination of deflection and crack widths. While often suitable for design purposes, the simplified methods approximate structural deformation at service loads without necessarily providing an insight into the time-dependent behaviour of the structure. In situations where accurate and reliable estimates of the effects of creep and shrinkage are required, the simplified methods of Chapter 3 may not be adequate. More refined methods are available that realistically model the time-dependent deformation of concrete structures and also enable the calculation of the redistribution of stresses between the concrete and the reinforcement and the redistribution of internal actions in statically indeterminate members. Refined methods for the time analysis of cross-sections are introduced in this chapter and illustrated using the simple example of a symmetrically reinforced cross-section subjected to a constant sustained axial compressive load.