Case 2
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- Introduction
- Causes of Defects
- Good Practices
- Standards
- Maintenance and Diagnostics
- Remedial
- Similar Cases
- References
Cause of Defects
- Many of these stains are related to the cleaning of brick masonry with hydrochloric acid solutions, especially if proper cleaning procedures are not carefully followed, i.e., thoroughly wetting the wall, method of applying the cleaning solution and thoroughly rinsing the wall with clear water.
- Rainwater that impacts the sliding window generating runoff to flow over the brickwall may also provide the source of water. The water may penetrate the brick from the top of the window sill and leach out the soluble salts at weak points in the mortar joints further below (Figure 1a, b and c).
- Silicate deposits are very difficult, if not impossible, to remove from brick masonry. They are insoluble in most acids. Often the only practical method of dealing with a silicate deposit is to disguise it and permit it to weather away over time.
- Silica staining by leaching of soluble silica fines to give white surface deposits (insoluble in most acids).