Waterproof ultra-high toughness cementitious composites containing nano reservoir silts

The waterproof ability of cementitious composites is essentially important for the uses in the aspects of construction, decoration and repair. Here we reported a waterproof ultra-high toughness cementitious composite (WUHTCC) that has the function of seepage resistance. The waterproof effect was improved by incorporating nano reservoir silts (NRSs) into the binders of WUHTCC. The mechanical properties, microstructures and water resistances of the WUHTCCs with different loadings of NRSs were tested to assess the affecting factors. The results show that increasing the loadings of NRSs maintains and/or enhances the toughness of WUHTCCs, but decreases the compressive strength. The water absorption is decreased, and the penetration pressure and time are increased significantly with increasing the NRS content. While the incorporation of NRS particles into cementitious matrix leads to a slight increase of porosity, it shows no significant changes of micro morphology. The variations of the mechanical and waterproof properties of WUHTCCs are induced by the hydrophobic and sheet-like NRS particles that alter the surface properties and microstructures of the material substrate. The WUHTCCs with good material properties developed in this study for seepage control facilitate their applications in the fields of construction, decoration and repair. (C) 2017 Elsevier Ltd. All rights reserved.