Influence of Flyash on expansive Soils

Infrastructure projects such as highways, railways, water reservoirs, reclamation etc. requires earth
material in very large quantity. In urban areas, borrow earth is not easily available which has to be Hauled
from a long distance. Quite often, large areas are covered with highly plastic and expansive Soil, which is
not suitable for such purpose. For this purpose the application of such expansive soil after Stabilization with
additives such as sand, silt, lime, and fly ash is used. As fly ash is freely available, for Projects in the vicinity
of a Thermal Power Plants, it can be used for stabilization of soils. In this project the Percentage of fly ash
is varied from 5 to 30 percent. The study from the laboratory test it concludes that with percentage addition
of fly ash improves the strength of stabilized clay soil. The compressive strength of soil is increased by
addition of fly ash content up to 1.600kpa. i.e., when the fly ash is increased (10 to 30) % the strength of soil
mix improved by 11%.The maximum shear stress of soil is improved by the addition of fly ash at
1.044KN/m2
(i.e., a 15% increase in shear stress)