blow count

blow count

1. The number of blows required to drive an object into soil. 2. In soil borings, the number of blows required to advance a sample spoon 6 in. (15.2 cm) or 12 in. (30.5 cm). 3. In pile driving, the number of blows required to advance the pile 12 in. (30.5 cm) or the number of blows per unit distance of advance.