Which pile top locations should be chosen for impacting the pile with the PIT hammer?

Generally, it is best to impact the pile in the center and measure at a distance of 2/3 of radius from the center. Keep in mind that ASTM D5882 limits the distance between impact and accelerometer to 300 mm or 12 inches. For piles with diameters greater than 500 mm, four measurement locations are needed (e.g., North, East, South, and West). For smaller piles, this is often not possible or necessary. Rather, at least two measurement locations for smaller piles are needed. The impact location should be as near to the shaft center as possible.