Effect of cellulose nanopulp on autogenous and drying shrinkage of cement based composites

Cellulose based materials, such as natural fibres, when added into a cement based matrix, can greatly affect the properties of the composite in its fresh state, early age and hardened state, including self healing capacity. This is due to their porous structure, hydrophilic character and water retention capability, which are likely to create additional moisture paths inside cement matrices. This paper focuses on the effect of nanoscale addition on the autogeneous and drying shrinkage of ce-ment mortars formulated from HPFRCC mixes. Two other different kinds of cel-lulose based additions were also studied for comparison, respectively eucalyptus micro fibers and natural sisal fibers, together with “conventional” steel fibres. This study is a part of a larger investigation undertaken by the authors in the frame-work of the EU-FP7 research project EnCoRe (www.encore-fp7.unisa.it) aimed at assessing the possibility of using cellulose based materials and natural fibers as promoters of self healing processes in advanced cementitious composites.