Drilling bucket - GIF

[Frank S]

Drilling some sandy soft soil I wonder what would happen if they hit a rock?

A lot depends on the type of rock. Crumbly gravel rock up to 3 or 4 inches they will keep digging might chance buckets or bucket bottom cutters soft shale limestone or sandstone, much the same even decomposed bedrock but once they hit a stratum of solid hard rock they stop drop in the rebar and pour the pilings If they don't hit a strata as solid as they need by the time they have reached max drill depth they might drop and under reamer to clean out the bottom of the hole to 3 times the bore hole diameter