Creep of Concrete Under Load

It is no exaggeration to say that the success of reinforced concrete as a structural material has depended very largely on the ability of concrete to adjust itself to stress conditions by means of creep. Scattered through the literature of reinforced concrete we find reference to this power of self -adjustment from the very early days of reinforced concrete construction, but it is only comparatively recently that the mechanism by which it operates has been investigated sufficiently to enable us to predict the progressive stress changes with some semblance of accuracy. It may well be suggested that this investigation, involving as it does all the factors producing progressive volume and length changes in concrete, has done more to extend our knowledge of the behaviour of reinforced concrete than anything else during the last decade. As a consequence, those who have studied these changes have learned to regard the assumptions we have to make in order to produce designs within a reasonable period from a new angle, and to realise that, although they serve reasonably well as a means to an end, they result in computed stresses that are, in general, very different from the actual stresses.

W.H. Glanville