Use of Molasses as Water Reducing and Retarding Agent in Concrete

Abstract

Pakistan produces approximately 50 Million tons of Sugar cane annually and most of it is used for production of Sugar. The industrial waste of Sugar cane, known as molasses, is used worldwide for the manufacture of alcohol. There have been many investigations about the effect of sugar on the hydrating properties of cement paste. There is a need to reduce the water cement ratio to increase the compressive strength. Water reducers help us to reduce the quantity of water for a given slump. It has been generally accepted that retarding action of sugar and their acid is due to the adsorption on the surfaces of hydrating cement grains as well as hydration products. This research study is carried out to evaluate the feasibility for the use of molasses in the concrete, as a water reducer and retarder admixture. The main variable in this research study are the amount of molasses and dosage of superplastisizer. The parameters those kept constant are the amount of cement content equal to 189 Kg/m3 and water-cement ratio equal to 0.68. Test results revealed that the concrete mixes containing molasses, showed higher compressive strength than Control Mix (CM). The concrete produced using molasses has exhibited excellent properties as water reducer and retarder. Government of Pakistan has allowed sugar mills to generate electricity through bagasse, this will produce large amount of molasses as industrial waste. The successful utilization of molasses as water reducing and retarding admixture in concrete would lower the cost of construction comparative to commercially available water reducer and retarders.