Adhesive loss usually comes from dirty or wet surfaces, laitance, old sealant residue, form release, missing or wrong primer, water repellent applied before sealing, or tooling that never pushed the sealant against the face. In the field it shows as a gap along one side of the joint. Pull tests and adhesion mock-ups catch it before a whole facade is sealed.
Sealant's let go of the precast on every joint, adhesive failure, I bet they never primed.
When adhesive failure shows only on one side of the joints, compare what that substrate needed against the primer actually used.
Also heard as
- adhesion loss
- adhesion failure
- AF
Related terms
Cohesive failure
A sealant tearing apart within itself while staying stuck to both joint faces.
Primer
A thin liquid brushed or wiped onto a joint face or deck so the sealant or membrane bonds reliably.
Laitance
A weak, powdery skin of cement and fines on the surface of concrete that sealants and membranes cannot hold onto.
Field adhesion test
A test that cuts a tab of cured sealant from an installed joint and pulls it to see whether it lets go of the substrate.