Pull off test for paintings and epoxy

The pull-off test, also called stud pull test in which an adhesive connection is made between a stud and the carrier (or object to be tested) by using a glue, possibly an epoxy or polyester resin, that is stronger than the bond that needs to be tested. The force required to pull the stud from the surface, together with the carrier, is measured. Simple mechanical hand-operated loading equipment has been developed for this purpose. When higher accuracy is required, tests can be performed with more advanced equipment called a bond tester. A bond tester provides more control and possibly automation. Applying the glue automatically and curing with UV light is the next step in automation. This methodology can also be used to measure direct tensile strength or/and the bond strength between two different layers.
Failure in the pull- off test for adhesion can either be a result of concrete substrate failure, as in the
current work, or a failure occurring between the layers of the particulate composite. Concrete substrate
failure is due to the adhesive force of the composite being greater than the cohesive force of the concrete,
while failure between the layers of a particulate composite is due to the inverse relationship. Failure,
occurring in the concrete (Figures 10 and 11) [9] suggests that the bond between the layers of the
composite and the concrete tensile strength are smaller than the concrete interface