Dynamic Properties of Indian Standard Sand and Coal Ashes from Cyclic Simple Shear Tests

Rapid increase in generation of ash products from coal-based thermal power plants have rendered these materials as an alternative to natural mineral resources in the field of geotechnical engineering. Fly ash and bottom ash are the two major ash materials produced from coal-based thermal power plants. When fly ash and bottom ash are mixed together and transported in the form of slurry and stored in lagoons, the deposit is termed as pond ash. Utilization of ash materials for various applications (reclamation, mine filling, retaining wall back fill material, and in pavements as a sub-base material, etc.) can alleviate disposal problems. When ash materials are used as a construction material and subjected to dynamic loading due to earthquakes, machine foundations, explosions, traffic movements, etc., it is important to obtain the dynamic properties shear modulus and damping ratio–at wide range of shear strains. The present study focuses on studying the behavior of bottom ash, fly ash, and pond ash subjected to cyclic loading using cyclic simple shear testing. In addition, the dynamic properties of ash materials are compared with Indian Standard (I.S.) sand. Dry sand and bottom ash specimens of 70 mm in diameter and 25 mm in height are prepared at relative densities equal to 30%, 50% and 75% and tested at a shear strain of 0.01% to 1% under vertical stresses equal to 100 kPa, 200 kPa, and 400 kPa