Aging and weather have negative influence on any structure. That is the law of nature. But can still be extended by regular monitoring and maintenance.

The structure is built up of concrete and rebar. There is not much argument in controlling the quality of the rebar, as it is approved by the structural engineer, based on the test reports and the reputation of the supplier’s quality assurance.

Always questionable practices arise in the production, supplying and laying of concrete. These can be controlled by the selection of,

• Cement, coarse aggregate and sand
• Water and admixtures
• Mix design
• Mixing plant, transport, and pump
• Leveling, compaction, and curing
• Weather

Any of the above or a combination of these factors will determine the strength of the structure.

The selection of the repair method and products are governed by the nature of the defects.