We were unable send the link to your email. Please check your email. The result of the Standard penetration test SPT is a number of blows N penetration resistance , needed to penetrate a sampling device to the soil or rock by a so-called Interval of penetration depth 0,3 m 1 ft. The number of blows N measured during the SPT test is correlated for the reason of various testing devices and for the influence of the weight of overburden in sand. Corrected correlated value N 60 is used in calculations. The correlated number of blows N 60 is calculated according to this equation:.
The test is carried out within a borehole. The results can be used to determine the relative density, bearing capacity, and settlement of granular soil. The results can also be used to correlate the approximate strength of cohesive soil. In cohesive soil the test involves driving a 50mm diameter split-barrel spoon sample tube into the ground to recover a disturbed sample.
Standard Penetration Test (SPT)-Procedure,Precautions, Advantages
The standard penetration test SPT is an in-situ dynamic penetration test designed to provide information on the geotechnical engineering properties of soil. This test is the most frequently used subsurface exploration drilling test performed worldwide. The test provides samples for identification purposes and provides a measure of penetration resistance which can be used for geotechnical design purposes.