Porosity of superplasticised cement paste containing limestone filler

Self-compacting concrete (SCC) can be placed without any external compaction avoiding some health risks as well as environmental problems. In order to obtain its key properties, a large amount of fine particles and a new generation of superplasticisers can be used. An experimental programme was set up to study the pore structure of SCC, including the influence of limestone filler and polycarboxylate ether superplasticiser. Mercury intrusion porosimetry (MIP) was used as a testing method. In this study tests were performed on samples of hardened cement paste of several ages in order to evaluate the relative influence of various parameters like water—cementitious (W/C), cement—powder (C/P) and water—powder ratio and to investigate the difference between traditional and self-compacting concrete. It was concluded that adding limestone powder as a filler and superplasticiser has an important influence on the pore structure of the cement paste. Decreasing the C/P and keeping the amount of water and powder constant induces a more porous cement paste. Increasing the W/C and keeping the amount of cement and powder constant leads to a coarser cement paste.