Standard Penetration Test

The Standard Penetration Test (SPT) is a commonly utilized in situ testing method that is employed to determine the geotechnical properties of subsurface soils. It is a straightforward and cost-effective test that is frequently utilized to estimate the relative density of soils and to approximately determine shear strength parameters.

Test Procedure

This test involves driving a standard thick-walled sample tube into the ground at the bottom of a borehole by blows from a slide hammer with a standard weight of 63.5kg and a falling distance of 760mm. The procedure is standardized and is performed under AS 1289.6.3.1-2004 to obtain accurate and reliable results.

Test Outcomes

The SPT blow count N-value provides an indication of the relative density of the subsurface soil, and it is used in empirical geotechnical correlation to estimate the approximate shear strength properties of the soils. The Standard Penetration Test (SPT) is a widely used method for determining the geotechnical properties of soil.

The SPT test is considered an effective means of determining the strength and stiffness of soil, which are important parameters in many engineering and construction applications. By conducting this test, engineers and geologists can make informed decisions regarding the design and construction of structures such as foundations, retaining walls, and embankments.