Kinetics of formwork pressure drop of self-consolidating concrete containing various types and contents of binder

A comprehensive research study was carried out to determine the effect of binder type and content on the variations in lateral and pore water pressures that can be exerted by self-consolidating concrete after casting and up to early stages of hardening. Test results show that both physical and chemical phenomena can influence the kinetics of the decrease in lateral pressure until cancellation. The former phenomenon occurs mainly during the dormant period of cement hydration, and is significantly affected by the binder type and content. Regardless of the binder type, the effect of increasing the binder content resulted in sharper drops in pressure. The cancellation of lateral pressure depends on a chemical effect and occurs after the end of the dormant period when the rate of cement hydration is accelerated. Beyond the dormant period, the progressive formation of hydration products leads to the creation of a structural network, and the pore water pressure begins to drop abruptly towards negative values. (c) 2004 Elsevier Ltd. All rights reserved.