Formwork Pressure of Highly Workable Concrete – Experiments Focused on Setting, Vibration and Design Approach
The presented investigations were conducted at the Institut für Massivbau and contributed to a joint research project including several German research institutes . A number of experimental tests on highly workable concretes were carried out. Small scale material analyses as well as measurements of the formwork pressure on large specimens were carried out. Based on the test results an analytical model for the calculation of the concrete pressure on vertical formwork was developed. The analytical model takes into account the time dependent material parameters of the fresh concrete, the specific properties of highly workable vibrated concretes and self-compacting concretes (SCC) as well as operation aspects. A proposal for the design of formwork, based on the experimental tests and the semi-probabilistic safety concept was developed. It was found that even for highly workable concretes, the design load is often lower than the hydrostatic concrete pressure.
KeywordsFriction Resistance Casting Rate Ultimate Limit State Friction Element Final Setting Time
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