International Journal of Latest Research in Engineering and Technology (IJLRET) ISSN: 2454-5031 www.ijlret.comǁ Volume 2 Issue 2ǁ February 2016 ǁ PP 40-48 www.ijlret.com 40 | Page POTENTIALS OF RICE-HUSK ASH AS A SOIL STABILIZER Sudipta Adhikary 1 . Koyel Jana 2 1& 2 Lecturer in Civil Engineering Department in Camellia School Of Engineering & Technology Barasat, Nadibhag, Kolkata:700124 Abstract: Rice Husk Ash is a pozzolanic material that could be potentially used in Soil stabilization ,though it is reasonably produced and freely available. When Rice-Husk is burnt under controlled temperature, ash is produced an about 17% -25% of Rice Husk‟s weight. This paper presents the results of experimental study carried out by the virgin soil sample was taken alongside the pond of “Jadavpur University”(Jadavpur Campus), Classified as CI( clay of medium plastic) as per AASTHO soil classification system and was stabilized with 5%,10%,15% & 20 % of Rice Husk Ash(RHA) by weight of the dry virgin soil. The improvement of the Geo- Technical properties of the fine grain soil with varying percentages of RHA was done with the facilitate of various standardize laboratory tests. The testing program conducted on the virgin soil samples by mixed with specified percentages of rice-husk materials, it is included Atterberg limits, “California Bearing Ratio(CBR)”, “Unconfined Compressive Strength(U.C.S)” , and “Standard Proactor test “.It was found that a general decrease in the maximum dry density(MDD) and increase in optimum moisture content(OMC) is shown with increase of the percentages (%) of RHA content and there was also a significant improvement shown in CBR and UCS values with the increase in percentages(%) of RHA. Key Words: UCS, CBR, RHA,OMC,MDD INTRODUCTION It is very common that the soil at a site is not ideal from the viewpoint of Geo-Technical engineering. An attractive approach which is generally employed to avoid many of the settlement and stability problems associated with soft soil, is the “ soil stabilization”. The soil improvement with different stabilizer (i.e .treatment materials or chemical additives) is one of the efficient way to enhance the geo-technical properties of virgin soil . In this method, the fine grain soil is mixed with the optimum proportion (i.e. effective dosage) of stabilizers, by the principle of mechanical compaction, in order to increase the durability and strength. Recently, a number of agro-industrial waste materials (Fly ash, sludge ash, bottom ash, rice husk ash etc.) have been very popular for use as soil stabilizer to improve soil characteristics, since they have a good pozzolanic activity with soil particles. In addition, that uses of such waste materials benefits the environment from the perspective of recycling sustainability. Rice is one of the most cultivated and consumed cereal in the world. In the rice producing countries a traditional waste material known as „rice husk‟ is obtained as a by-product in bulk amount from Rice mills. Such rice husk is available in most part of the Indo-gangetic plane in India . Globally, approximately 600 million tones of rice paddy are produced each year. On average 20% of the rice paddy is husk, giving an annual total production of 120 million tones (www.berr.gov.uk). Rice husk is being used in making mud walls from ancient time in many countries. In the majority of rice producing countries like India and China, much of the husk produced from the processing of rice is either burnt or dumped as a waste. However a majority of mills use the rice husk as fuel to generate steam to parboil rice with very low combustion efficiency; and as a by-product rice husk ash is produced. Rice husk ash is being generated in yearly frequency at large quantity and about 20 million tonnes of RHA is produced annually throughout the world (www.ricehuskash.com) and is commonly left as waste materials. Rice husk ash has many applications due to its various properties. A pozzolan is a powder material , which when added to the cement in a concrete mix reacts with the lime, released by the hydration of the cement, to create compounds which improve the strength or other properties of the concrete (Logicsphere concrete Design Software, 2003; King,2000;Lohita and Joshi,1995). RHA is a highly pozzolanic material; it contain non crystalline silica and high specific surface area that are accountable for high pozzolanic reactivity (Della et al 2002). Upto now, the utilization of RHA in sub grade soil as a soil stabilizer with conventional additive materials (Lime, Cement) has been research extensively. However, the number of researchers on the usage of it as a soil stabilizer without using any conventional additives for the stabilization of the fine grain soil is rare. So, utilization of such material for improving the engineering properties of fine grain soil needs to be investigated.