Architectural Ceramics
Author: Hans-Jürgen Schwarz
English Translation by Sandra Leithäuser
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Abstract[edit]
Typical deterioration patterns for architectural ceramics are discussed and explained.
Decay patterns of architectural ceramics[edit]
Deterioration of brickwork
Salt-induced damage to bricks is common.
Damage to bricks can appear as follows:
Glazed architectural ceramics
The glaze on building ceramics prevents the transport of moisture and salts. Often however, the glaze shows "crazing" (a fine network of fissures or cracks) allowing moisture transport through it. And therefore, if salts are present, they will crystallize around these fissures as well as below the glazing around them, leading to their spalling.
Some examples of salt-contaminated glazed building ceramics are shown here.
Flaking[edit]
Figure 3: Photo micrograph as Fig 2 with crossed polarizers. It is clearly visible that, on the one hand gypsum is causing the damage to the brick, but on the other hand it acts like an adhesive/ cement, holding the flaking pieces in place. With the removal of the gypsum the original substance of the brick would be lost.