DefinePK

Abstract

In this study, a series of small and large scale direct shear tests were conducted to evaluate the effect of mixing fly ash in two ratios i.e. 20 and 25% by volume on the shear strength behaviour of coal mine overburden dump rock and these results are compared with direct shear tests conducted on overburden dump material without fly ash. The effect of mixing fly ash on stability of both internal and external overburden dumps were assessed with FDM based slope stability software using determined shear strength parameters and dump slope angle were optimized for safe disposal of the fly ash by mixing it with overburden dumps in the coal mines. The investigation carried out as above revealed that fly ash mixed internal and external overburden dumps having an overall slope angle ranging between 24 to 280 in two benches of 30 m height is stable and disposal of fly ash can be carried out safely by mixing it with the coal mine overburden rock material.