Silica fume in cement and silicate grouts and grouted sands

The behavior of silicate and cement grouts and grouted sands with silica fume additive was investigated. The effect of silica fume content on the working and mechanical properties such as setting time, bleeding, viscosity, adhesive strength, compressive strength and tensile strength of the grouts was studied. The stress-strain relationship for grouted sand under unconfined compression was investigated up to 28 days of curing. Addition of 5\% silica fume to cement and silicate grouts considerably reduced the bleeding and syneresis of the grouts, respectively. Addition of silica fume as a filler to bath cement and silicate grouted sands enhanced the mechanical properties. Silicate grout strength and bonding strength were not significantly affected by silica fume.