Geotechnical Investigations

Geotechnical investigations are performed by trained staff including geotechnical engineers to obtain information on the physical properties of soil or rock.  A geotechnical investigation will often include surface exploration including a walkover survey to observe existing conditions and performance of existing structures and subsurface exploration of a site using drilling or other excavation methods. Subsurface exploration usually involves soil sampling, in situ test and laboratory tests of the soil samples retrieved.

Part of the investigation may include, In-situ probing to enable the assessment of engineering parameters of the ground:

• Plate bearing test.
• California bearing ratio.
• Light/Heavy weight deflectometer or Falling Weight Deflectometer (FWD)
• Density measurement.
• Standard penetration test (SPT).
• Dynamic penetration tests, such as the dynamic cone penetrometer – DCP (refer toAS 1289.6.3.2) or the Perth sand penetrometer (refer to AS 1289.6.3.3).
• Specialized cone penetration tests, such as the static cone, piezo cone, electricalconductivity cone, and seismic cone.

Geotechnical Investigation is very important before any structure is built.  A detailed investigation will often lead to lower risk and/or lower project over-runs.