Lateral stress exerted by fresh cement paste on formwork: Laboratory experiments

In the present paper, experimental results from laboratory testing on cement pastes are presented. The validity of both the predictions of the model proposed by Ovarlez and Roussel [Mat. and Struct. 39(2) (2006)] and the assumptions on which the model is based in the case of rough interfaces between the cement paste and the formwork surface are validated. The consistency of the underlying theory is tested in several different configurations (plate test with large and narrow gaps and a column test). Finally, the concept of a new test allowing the measurement of the structuration at rest of a cementitious material is proposed. Such a simple test might be used to assess the input parameters needed to predict formwork pressure without the need for a rheometer.