Estimating the exact formwork pressure for self-compacting concrete (SCC) remains an unsolved issue for building contractor and formwork supplier. In practice, it is often advised to use the hydrostatic model for formwork calculations. This sometimes leads to an overestimation of the formwork configuration and extra costs, especially in the case of high construction elements. On the other hand, some research projects describe the successful attempts to use special types of admixtures for obtaining a decrease of this formwork pressure. In those cases, the thixotropic properties in the concrete may eliminate part of the pressure. In this research project, the BBRI evaluated the practical application of the following questions: the influence of some relevant mixture properties on the pressure, the potential thixotropic behaviour decreasing the formwork pressure and the feasibility of measuring this pressure during the casting process. Several measuring devices were used and evaluated, in order to propose an efficient monitoring tool for the building site. Monitoring the pressure could be an economical and efficient tool to use the full potential of the formwork configuration, without having the risk of serious deformations or even failure. The developed devices were used for monitoring the casting of real-scale walls, in order to evaluate the influence of parameters such as casting rate, reinforcement ratio and type of SCC.
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