What it involves
The Standard Penetration Test (SPT) is one of the most widely used in-situ tests in geotechnical engineering: a 63.5kg slide hammer dropped 760mm per AS 1289.6.3.1-2004, with blow counts converted into relative density and shear strength estimates. It's a core input for foundation sizing and retaining wall design across Melbourne, regional Victoria and the Greater Brisbane area, and is often run alongside drilling as part of a broader site investigation.
Applications
- Relative density estimates
- Shear strength inputs
- Foundation sizing
- Retaining wall design
What you receive
- SPT N-value logs
- Empirical strength correlations
- Engineering parameters
Method & standard
63.5 kg slide hammer, 760 mm drop, per AS 1289.6.3.1-2004. Carried out to AS 1289.6.3.1 by Probegeo's MIEAust-certified engineers.
Where we provide this service
Standard Penetration Test (SPT) is available across the Greater Melbourne area and regional Victoria, plus the Greater Brisbane area as a mobile, BPEQ-registered operation.
- Melbourne & regional Victoria
- Brisbane & South East Queensland
Common questions
What does an SPT actually tell my engineer?
SPT N-values give empirical correlations to soil density and shear strength, which feed directly into foundation sizing calculations and retaining wall design parameters.
Is SPT the same as DCP testing?
No — SPT is run inside a borehole at depth and is standard for foundation design on larger or deeper structures, while DCP (Dynamic Cone Penetration) is a faster, portable near-surface test often used for pavements and early-stage investigations. We offer both.