Pile integrity testing for concrete piles and shafts
- Pile integrity test (PIT), or as ASTM D5882 refers to it as "a low strain impact integrity test," is a common non-destructive test method for the evaluation of pile integrity and/or pile length.
- A pile integrity test can be used for forensic evaluations on existing piles, or quality assurance in new construction.
- The Integrity test is applicable to driven concrete piles and cast-inplace piles
- Low strain impact integrity testing provides acceleration or velocity and force (optional) data on slender structural elements (ASTM D5882).
- Sonic Echo (SE) and Impulse Response (IR) are employed for the integrity test on deep foundation and piles.
- Integrity and consistency of concrete piles;
- Evaluate Unknown length of piles, or shafts;
- Pile cross-sectional area and length.
- The integrity testing should be performed no sooner than 7 days after casting, or after concrete strength achieves at least 3/4 of its design strength, whichever occurs earlier.
- The pile head surface should be accessible, above water, and clean of loose concrete, soil or other foreign materials resulting from construction. Any type of contamination should be removed to reach to solid and sound surface. The sensor should be placed away from the edges of the pile.
- An impact source (usually a hammer) is used to impact the pile head; the impact should be applied axially with the pile. Motion transducers should be capable of detecting and recording the reflected echos over the pile top.
- The sensor should be placed away from the edges of the pile and the distance between the impact location and the sensor should be no larger than 300 mm. Several impacts are applied to the top of the pile. The reflected echos are then recorded.