What is under ream pile?

Underreamed piles have mechanically formed enlarged bases that have been as much as 6 m in diameter. The form is that of an inverted cone and can only be formed in stable soils. The larger base diameter allows greater bearing capacity than a straight-shaft pile.

These pile are suited for expansive soils which are often subjected to seasonal moisture variations, as also filled up ground and loose or soft strata. They are used in normal ground condition also where economics are favorable.