Case 2
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- Introduction
- Causes of Defects
- Good Practices
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- Maintenance and Diagnostics
- Remedial
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Cause of Defects
Concrete is not a waterproofed material. It consists of micropores formed during the migration of excess water during the hydration process. As the excess water dries off, they form channels or capillary pores. When subjected to water pressure, the pores allow the passage of water, resulting in seepage. The porosity of concrete, coupled with crack lines, allows the ingress of water, and, when re-surfaced, may result in the formation of efflorescence (deposit of salt) and/or calthemite (deposit of calcium carbonate). This is exacerbated by the formation of cracks due to the weak tensile strength of concrete against stresses resulting from shrinkage, differential settlements, etc.
Alkali-Silica Reaction (ASR)
