ABSTRACT
Durability of building materials is related to the presence of cracks since they provide a fast pathway to the transport of liquid and gasses through the structure. Restoration and preservation of historical buildings has been investigated through the application of novel cementitious materials using nanoparticles such as nano-silica and silica fume. Injection of nano-silica was carried out at a low water pressure in hydrated cement paste. This novel technique can tailor mechanical and hydraulic properties of existing building materials simply and non-destructively. The formation of cracks and increased porosity from leaching in concrete and cement paste presents an easy pathway for the ingress of moisture. Cement samples were prepared mixing Portland cement and deionized water at a water to cement ratio of 0.41. The mixing of cement and water was made in a rotary mixer according to BS EN 1961:2005.
