Adhesion, mechanical Adhesion between surfaces in which the adhesive holds the parts together by interlocking action. Adhesion, specific Adhesion between surfaces which are held together by valence forces of the same type as those which give rise to cohesion. Admixture A material other than water, aggregates, and hydraulic cement, used as an ingredient of concrete or mortar, and added to the concrete immediately before or during its mixing. Alkali A chemical substance which effectively neutralizes acid material so as to form neutral salts. The opposite of acid.
Examples are ammonia and caustic soda.
Backing Any material used as a base over which a finished material is to be installed. Bisque cracks Any fractures in the body of a tile visible both on the face and back. The adherence of one material to another. Effective bonds must be achieved between the mortar and scratch coat, between the tile and mortar, and between the adhesive and backing. A substance applied to a suitable substrate to create a bond between it and a succeeding layer as between a subsurface and a terrazzo topping or a succeeding plaster application.