Shrinkage, Swelling and Creep in Cement

Graphs, based on observations of shrinkage and swelling of cement prisms subjected to various conditions of drying and wetting, are presented. The abscissae of the graphs represent the internal volumes emptied or filled by the liquid, and the ordinates represent the corresponding changes in length of prisms. From this experimental evidence, an explanation for the volumetric changes in the form of the active water theory is suggested. In addition to an analysis of the mechanical action of film water in the light of theory, some further experimental evidence in support of the theory is presented. The usefulness of the volume-shrinkage graphs is indicated.