International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 07 Issue: 03 | Mar 2020 www.irjet.net p-ISSN: 2395-0072 © 2020, IRJET | Impact Factor value: 7.34 | ISO 9001:2008 Certified Journal | Page 4276 Enhancement of Shear Strength of Sand-Slag Mixture Using Wood Sticks Athirasree K. R. 1 , Arun K. U. 2 , Sreevidhya V. 3 , Anju E. M. 4 1 Student, Department of Civil Engineering, IES College of engineering, Thrissur, Kerala, India 2 Student, Department of Civil Engineering, IES College of engineering, Thrissur, Kerala, India 3 Assistant Professor, Department of Civil Engineering, IES College of engineering, Thrissur, Kerala, India 4 Assistant Professor, Department of Civil Engineering, IES College of engineering, Thrissur, Kerala, India ---------------------------------------------------------------------***---------------------------------------------------------------------- Abstract - Sand is a granular material, composed of finely divided rock and mineral particles. In certain situations, sand is required to have extra shear strength to provide more safety, stability and support for structures. Shear strength in sand arises from friction and resistance between particles. The most common means of increasing the shear strength of sand is the cementation method and addition of slag. Some studies show that wood has also been used to improve soil strength, mostly for soft and expansive soil. However, there is limited information available on sand. Therefore, the purpose of this research is to determine whether the shear strength of a sand-slag mixture is affected by the addition of wood. The shear strength of the sand-slag-wood material was determined using a direct shear testing machine. The results showed that the shear strength of the sand-slag mixture tended to be enhanced by the presence of wood. The sand-slag mixture containing wood seemed to be stronger than the sand-slag without wood or the pure sand. The position of the wood also contributed to the improvement in shear strength. From these results, it can be concluded that wood is another potential means of enhancing the shear strength of sand- slag mixture. GGBS slag gave best shear strength when 2% slag used with sand in dry condition and 3% in wet condition. As the quantity of wood increases, and the way its arrangement changed, such as distance and direction, resulted in improvement of the shear strength of the sand- slag mixture. Key Words: Wood sticks, Sand- slag, GGBS slag, Shear strength, River sand. 1. INTRODUCTION Sand is a granular material that composed of finely divided rock and mineral particles. It is defined by size, being finer than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; that is, a soil containing more than 85 percent sand-sized particles by mass. The composition of sand varies, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non- tropical coastal settings is silica (silicon dioxide, or SiO 2 ), usually in the form of quartz. The second most common type of sand is calcium carbonate, for example, aragonite, which has mostly been created, over the past half billion years, by various forms of life, like coral and shellfish. For example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Soil Stabilization is the alteration of soils to enhance their physical properties. Stabilization can increase the shear strength of a soil and/or control the shrink-swell properties of a soil, thus improving the load bearing capacity of a sub-grade to support pavements and foundations. Soil stabilization can be done with cement, bitumen, lime, chemical stabilization, geotextile, grouting etc. It is a method of improving soil properties by blending and mixing other materials. 1.1 Soil stabilization using slag and wood Ground-granulated blast-furnace slag (GGBS or GGBFS) is obtained by quenching molten iron slag (a by-product of iron and steel-making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder. It is a granular product with very limited crystal formation, is highly cementitious in nature and, ground to cement fineness, and hydrates like Portland cement. GGBS is used to make durable concrete structures in combination with ordinary Portland cement and/or other pozzolanic materials Adding GGBS to sand had shown significant improvement in its strength properties. Shear stress or shear strength of the soil is a very important factor in reviewing the stability of the soil. Shear strength is mainly influenced by two soil shear strength parameters, namely the cohesion and friction angle. Soil shear strength is important in analyzing the stability of a slope and analysis of the subgrade bearing capacity of the foundation. Therefore, soil strength analysis and careful design are required to avoid structural failure arising from the collapse of the soil structure and prevent the undermining of the basic foundation of the structure built upon it. There has been an increase in the use of chemicals (chemical additives) for land improvement, such as cement lime, slag and fly ash, due to the ease of use of