In a standard penetration test, a medium dense sand typically has a blow count of:

In a standard penetration test (SPT), the blow count is a measure of the resistance of soil to penetration, which is particularly useful for characterizing soil strata. For medium dense sand, a blow count in the range of ten to thirty is typical. This reflects the ability of the sand to resist penetration under dynamic load conditions during the test.

Medium dense sand provides enough resistance to indicate that it has a good amount of particle interlocking and cohesion, leading to this specific range of blow counts. Values below ten often indicate loose sand, while values above thirty usually suggest that the sand is becoming dense or very dense. The blow count is directly correlated to the relative density of the sand, allowing engineers to gather significant information about the soil's properties and the necessary design considerations for foundations and excavation.