Data on the Magnitude of Strain

Abstract

As a rule, it is not necessary to know the modulus of elasticity of concrete E_c with precision in order to determine the stresses and action effects caused by loads. It is enough to use the approximations according to Section 3.1.4. However, it is another matter when imposed or internal stresses occur, for instance, in the case of prestressing. This applies particularly when the concrete is strained at a very early age, since the data given in Section 3.1.4 are valid for 28-day-old concrete. In addition, the type of aggregates and the rate of loading often have an effect that can no longer be disregarded, even when considering only the domain of normal concrete. More precise information on E, is also of importance for an estimate of deflections.