An investigation of rheological properties of cement-based grout mixed with rice husk ash (RHA)

• Rheology of cement base grout treated with rice husk ash was studied.
• The addition of RHA to cement base grouts significantly modifies the rheological properties.
• An increase in the RHA content reduces the mini-slump flow diameter.
• An increase in the RHA content increase the marsh cone flow time.

This paper investigates the fluidity and rheological properties of the cement based grout mixed with rice husk ash (RHA). The experimental program consisted of fifteen different mixture having 5%, 10%, 20%, and 30% RHA content and three different water to binder ratios (w/b = 0.75%, 1.00%, and 1.25%). Workability properties (marsh cone flow time, plate cohesion, and mini slump diameter), plastic viscosity, apparent viscosity, and the yield stress of the mixtures were determined. Test results showed that increasing replacement level for the RHA amount increases marsh cone flow time, plate cohesion, plastic and apparent viscosity, and the yield stress, but also decreases mini slump diameter. Shear thickening and pseudo-plastic behavior was observed for high RHA content for w/b ratios greater than 1.00.