Effect of Rice Husk Powder content with different watercement ratios on rheological properties of cement-based grouts

It is appear that a lot of waste materials producted during industrial production in all over the world. There is a difficulty for storing and removing these products. Moreover, they cause pollution of the environment. One of the huge waste products is rice husk. Every year nearly 400 million tons of waste rice husk produced in the world. The rice husk has been used for different purposes such as a fuel in brick kilns, in furnaces, as an cleaning or polishing agent in metal and machine industry, in the manufacturing of building materials. In addition, rice husks themselves are a class A thermal insulating material because they are difficult to burn and less likely to allow moisture. Its ash is also replaced with cement as a cementitious material in concrete production In this study, feasibility of use of rice husk powder (RHP) as filler in cement grout was investigated. For this purpose rice husk was grinded to certain grain size and mixed with cement grouts at 4, 8, 12, 16 and 20% respectively. The mixture were prepared at different water to cement ratio (0.75, 1.00, 1.25 and 1.50). Effect of RHP on fluidity and rheological properties of the cement grout mixtures were studied. Test results showed that at water cement ratio (w/c) of 0.75, 1.00, 1.25 mixture showed shear thinning behavior. On the other hand, this behavior changes to shear thickening behavior at w/c = 1.50 at all RHP content. Experimental results indicated that this waste product can be utilized as filler in cement grout for geotechnical application such as filling large voids.