Title: Formwork Pressure Model for Self-Consolidating Concrete Using Pressure Decay Signature
Author(s): Jacob D. Henschen, Daniel I. Castaneda, and David A. Lange
Publication: Materials Journal
Appears on pages(s): 339-348
Keywords: formwork pressure; predictive model; self-consolidating concrete
Industry guidelines recommend that formwork be designed to withstand full hydrostatic pressures when using self-consolidating concrete (SCC) and highly flowable concrete. However, full hydrostatic pressures are seldom observed during SCC pours, meaning that it is possible to safely relax formwork design specifications. Numerous researchers have developed models that incorporate lab-tested material values to predict formwork pressure, but these models are affected by changing concrete mixture design, air temperature, humidity, and other factors that cannot be accounted for quickly. A simple field test method and model is presented in this study that predicts the formwork pressure using a calibrated behavior, which we call a “pressure decay signature.” The simple formwork pressure model is shown to agree well with experimentally measured values during the construction of two
tall-walls, suggesting that this method and model can contribute to increased cost efficiency of SCC construction while maintaining safe practices.