SOIL STABILIZATION USING PAPER MILL SLUDGE ASH AND SAW DUST ASH by Jasvir Singh
One of the most problematical soils are expansive soils which are found on every part of earth except polar zones. One of the main problem is their shrinking and swelling behaviour when they come in contact with water. When structures are constructed on these soils, these causes differential settlement which may cause economic burden on developers. Structural stability comes in danger if proper remedial measures are not taken. Many methods and techniques are used to prevent harm caused by these soils. One of best technique which is used since old times, that is soil stabilization. In ancient times additives are added in soils to stabilize it. Now a day many other additives like polymers, waste materials, salts etc. are used to stabilize soil with combination of basic additives like cement, lime, fly ash, bitumen etc. Proper gradations of these additives are added for treating the soil effectively. At present-day waste management is a big problem for industries which is increasing gradually. Many researchers are doing research to use waste materials for soil stabilization which can solve both problems, soil stabilization and waste management. These researches are based on fact that to understand the reaction between lime rich wastes and soil. This study was thus done to study the effect of lime-rich paper mill sludge ash and saw dust ash on properties of expansive soils. Main Properties which are investigated was California bearing ratio and strength. Unconfined strength test was performed to inspect the strength of soil. Also in this test stress strain curve was drawn to check whether material is becoming brittle or ductile with the addition of waste materials. CBR was performed also performed to check suitability of soil for subgrade in flexible pavement. Apart from these properties, the other engineering properties which examined were moisture content and dry density of soil which was needed in UCS and CBR and also atterberg limits and grain analysis of soil sample. Materials which are used for study accompanied by soil samples were paper mill sludge ash which results from burning of sludge produced in paper mills and saw dust ash which produced after burning saw dust. In this study it was noted that soil treated with both two ashes is related to soil treated with lime and cement.