Can steel piles be tested with the PIT?
The PIT is less suited for testing steel piles. Generally, steel piles have a high L/D ratio. Furthermore, steel piles typically present a high surface area to volume ratio. The surrounding soil quickly dampens the input wave because of this ratio. For more information on the difficulties associated with performing low strain dynamic tests on large L/D ratios, based on the sonic pulse echo or transient response theory on piles, click here. The PIT equipment and software allows for wave speed and specific weight modifications to correspond with steel piles.
The PIT test is most suited to determine the integrity of concrete foundation elements. Nevertheless, some have reported success in identifying defects on short (less than 15 m or 50 ft) H-piles in soft soils. PIT is not recommended for open steel pipe piles unless they are filled with concrete.