Case 2
Navigation
- Introduction
- Causes of Defects
- Good Practices
- Standards
- Maintenance and Diagnostics
- Remedial
- Similar Cases
- References
Cause of Defects
- All new constructions would experience settlement due to exertion of loads on the freshly compacted soil for the initial 5 years of its life. In general, settlement would not threaten the structure’s integrity whereas uneven settlement would give signs of structural deterioration via cracking.
- Structural elements could be subjected to periodical expansion and contraction due to the difference in temperature during day and night time. Thus, cracks may result due to the lack of provision of movement joints.
- When water pressure builds up against the concrete structure, joints or these crack lines will present a relief point. Absence of a waterproofing system allows ground water to seep onto the basement floor through capillary action.
- Poor maintenance might have contributed to the origination of water seepage and the subsequent formation of the efflorescence. This is due to the failure in taking adequate corrective maintenance for the crack over a long period of time.
Basement water seepage – courtesy of DryProof
- 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.
