16/04/2026
Standard Pe*******on Test (SPT) is a widely used in‑situ geotechnical test carried out during borehole drilling to assess the strength and density of subsurface soils. In this test, a standard split‑spoon sampler is driven into the ground at the bottom of the borehole using a 63.5 kg hammer freely dropped from a height of 760 mm, and the number of blows required to pe*****te each 150 mm interval is recorded. The sum of blows for the second and third 150 mm intervals is reported as the “N‑value” or standard pe*******on resistance, which is then correlated with soil properties such as relative density in sands, undrained strength in clays, bearing capacity, and pile design parameters. SPT is economical, simple to perform, and also provides disturbed soil samples for classification, making it one of the most common tests in geotechnical site investigation for foundation and geotechnical design. Zaman Engineering Services
