This document discusses using foundry sand and rice husk ash to stabilize soil. Standard proctor tests were conducted on soil mixed with different percentages of foundry sand and rice husk ash to determine optimum moisture content and maximum dry density. The tests found that:
1) As the percentages of foundry sand and rice husk ash increased, the optimum moisture content of the soil increased while the maximum dry density decreased.
2) Rice husk ash, which contains silica, can reduce the shrinkage and swelling properties of clay in soil.
3) Mixing foundry waste and rice husk ash into soil led to an overall improvement in the soil's engineering properties, showing it is an effective and low-