Rotary Drilling

Rotary drilling is a site investigation technique which involves borehole drilling by rotary methods to depths of 1->100m. Traditionally, a 1.50m hollow steel tube with diamond teeth is cut into the underlying rock. The core barrel is retrieved after each 1.50m run, and rock samples are obtained. This type of drilling is useful for understanding ground conditions at depths which exceed the maximum reach of methods such as dynamic sampling and trial pitting.

Whereas dynamic sampling cannot penetrate bedrock, rotary drilling rigs can and are therefore for aiding pile design, and also for installing groundwater monitoring standpipes.

At GCL we favour the Comacchio 205 drilling rig.

Comacchio GEO205 Specifications:

• Minimum Width: 1100mm
• Minimum Height (mast down): 2100mm
• Minimum Height (mast up): 4700mm
• Minimum Length (while set-up): 3300mm
• Minimum Weight: 2600kg
• Max Drill Depth: 60m