LOK-TEST
The LOK-TEST system is used to obtain a reliable estimate of the in-place compressive strength of concrete in newly cast structures in accordance with the pullout test method described in ASTM C900, BS 1881:207 or EN 12504-3,
An insert with a steel disc, 25 mm in diameter at a depth of 25 mm, is cast into concrete. Once the concrete has hardened, the disc is pulled centrally against a 55 mm diameter counter pressure ring bearing on the surface. The force F required to pullout the insert is related directly, through a robust general correlation, to the compressive strength of concrete. Loading is performed either to a required force, in which case the test is nondestructive, or to the peak-load, which results in a slightly circular crack on the surface.
