Treatment of Peaty Clay by High Energy Impact

For a warehouse construction in Singapore, 3 m to 4.5 m depth of peaty clay overlain by 3.5 m to 6 m of medium silty clay posed a problem for the foundation construction. In order to avoid excessive settlements for the foundation and the floor slab, the methods available were to drive piles to a good bearing and suspend the flooring or to replace the highly compressible peaty clay with a better soil type which could be compacted to receive the spread footings and flooring slab. For the small column and floor loads involved, both these approaches were found to be expensive and the latter method was also impractical for the site conditions. The method of applying high energy impacts on the top of the silty clay layer overlaying the peaty clay was adopted in order that the improvement in strength and compressibility characteristics could be brought about for the peaty clay to the desired levels.