7. Conclusions

Peel tests (based on the use of a reinforcing membrane) and fracture surface characterizations were effectively combined to measure adhesion and study bonding between bitumen and aggregate (depending on rock mineralogy), and between paint-type protective coating and concrete surface. The peeling method developed, involving the insertion of a flexible membrane into the mass of the organic layer to be peeled, enables efficient and reproducible measurement of the peeling forces between the organic material (composed of bitumen or polyurea coating) and the mineral substrate (composed of aggregates or concrete, respectively).

After an ageing process under water to initiate debonding, the crack propagated exclusively in the bitumen mass during peeling on dolomite-type rocks, whereas crack propagation took place more at the interface in the case of granitic rock. In addition,...