Drilling Refusal Definition

[aayjaber]

Requested a quote for drilling piers in rock, the drilling contractor has pretty big heavy duty machines. My requirement for drilling is 3 ft in competent rock or drilling refusal. The drilling contractor refusal is when his drill does not go more than one ft in five minutes. Is this a reasonable definition?

 

[Ron]

Yes.

 

[DRC1]

At what torque?

 

[eekgec]

drill size? is the driller proposing to use a "rock" bit and/or core barrel? soil/rock type?

 

[GeoPaveTraffic]

You should also require that the minimum penetration is not achieved under full down pressure. If you expect more than one company to bid, then you need to define the equipement or torque.