Shear strength characteristics of some Indian fly ashes

Thermal power stations using pulverized coal as fuel produce enormous quantities of ash as waste products of combustion. In India, it is estimated that thermal power plants will produce about 100 million t of flyash per year by the year 2000. Hence the problem of ash disposal is expected to become acute due to the limited space available for ash disposal near most of the power plants. This calls for strategies to encourage and establish technological concepts for bulk utilization of fly ash which should not only be cost-effective but also environment friendly. This paper reports an experimental programme carried out to study the shear strength characteristics of fly ash using direct shear tests under different conditions so as to enable its bulk utilization in geotechnical engineering applications. The results are encouraging due to the low unit weight, good frictional properties, low compressibility and high permeability of fly ash.