What does spalling refer to in construction materials?

Spalling refers specifically to the chipping or flaking away of material from the surface of concrete or masonry. This phenomenon often occurs due to the effects of moisture infiltration, freeze-thaw cycles, or chemical reactions that lead to internal pressure within the material. When the outer layer of concrete or masonry breaks away, it can compromise the structural integrity and durability of the material, making it a significant concern in construction and building maintenance.

A is focused on glass, which does not relate to spalling in the context of this question, as spalling is primarily a term used with concrete and masonry. C refers to the deformation of structural components, which is unrelated to the definition of spalling. D mentions peeling paint, but this is a different process entirely and not linked to the behavior of construction materials like concrete or masonry. Thus, the most accurate definition related to spalling is indeed the chipping and flaking of concrete or masonry.