J. Phys. IV France 110 (2003) 447
Experimental analysis of fresh concrete under dynamic loadingS. Pattofatto1, H. Zhao1 and A. Poitou2
1 Laboratoire de Mécanique et Technologie, ENS de Cachan, CNRS, UPMC, 61 avenue du Président Wilson, 94235 Cachan cedex, France
2 Laboratoire de Mécanique et Matériaux, École centrale de Nantes, UPRES EA 2166, BP. 92101, 44321 Nantes cedex 3, France
This paper presents a new experimental technique to study the behavior of fresh concrete submitted to a shock pulse. The aim is to determine the source of the efficiency of dynamical compaction. The test is based on the Hopkinson bars technique. The apparatus is vertical and allows to apply successive impacts on the specimen. Moreover, it allows the indirect measurement of stress and velocity at the interaces between the specimen and the bars. First, measurement technique is validated. Then, the first experimental results are presented: measurement of the velocity of the wave propagating into the material, depending only of the density; and analysis of the efficiency of dynamical compaction compared to quasi-static compaction.
© EDP Sciences 2003