FRANKI FORUM BORED PILES
This versatile pile type also referred to as a bored pile or percussion bored pile, is suited to sites that are congested, remote, have limited headroom or uncertain ground conditions.
Bored piles are formed by percussion driving segmental coupled casings and excavating the soil inside the casing with a coring tool. On attaining a suitable pile depth, which may be determined by inspection of the excavated soil, a dry cast bulbous base is formed. The shaft may be formed by filling the empty bore with high slump concrete or alternatively by drop hammer compacting successive charges of ‘dry’ concrete while at the same time withdrawing the temporary casing. The process of forming a bulbous base and dry casting the pile shaft has the effect of conditioning the surrounding soil and optimising the load capacity of the pile. Bored piles can also function as end bearing piles on rock and suitable rock sockets can be excavated by use of specialised rock chisels.