Concrete floor slabs are commonly seen in heavy traffic compounds such as industrial and commercial building sites as well as outdoor areas like car parks and roof terraces.

Concrete floors are critical especially for factory sites such as warehouses and production and garage floors due to the frequent vehicular traffic access day to day, and so the concrete surfaces are subjected to weight load, impacts, climatic conditions, chemical reactions, abrasions and other wear and tears. As such. problems such as delamination or spalling, cracking or crazing (craze cracking), curling, peeling, etc, occurs over use and over time. These defects and imperfections can be resolved by applying concrete floor coatings and resurfacing, including epoxy paint for flooring to give them a new lease of life and strength.

Spalling Concrete Flooring or Delamination

Spalliing concrete or delamination in concrete happens when thin pieces of concrete begin to flake and fall off the surface randomly, resulting in an uneven, patchy and dis-leveled surface. It is usually caused by hollowness beneath the surface of the concrete slab due to poor finishing of the concrete slab surface done previously, i.e. the concrete finishing works was done before the underlying layer had been cured (incomplete bleeding) completely. This may be caused by the finishing layer has been sealed in too early, or that there is improper concrete mix that could result in not drying uniformly but faster on the surface than its consistency below, hence trapping air and moisture in the slab’s thickness, weakening the surface and affecting the bonding of the concrete layers as a whole.

A test for concrete delamination can be done by knocking on the concrete surface, if it returns an almost echo-y sound, it is normally an indication of the presence of hollow spots and that the setting of the concrete surface has not been done properly and delaminating could occur.

Concrete Cracking or Crazing

Concrete cracking or crazing basically means cracking or fissuring in a particular pattern, usually widespread, across the concrete surface, largely due to drying shrinkage. This is most commonly seen in drier and hotter places with low humidity, or where there are expansion or contraction movements, and stress between the surface and underlying layers is experienced.

This could be due to poor curing process or the quality of the concrete mix. Concrete mix that has moisture trapped and not evaporated off weakens the concrete’s strength and increases the chances of shrinking. As concrete tends to shrink upon drying, there is tension going on in the concrete during this hardening process. If the finishing and under layers are not bind properly, craze cracking can occur over time.

While craze cracking in concrete does not affect its structural integrity, these cracks could provide opportunities for grease, moisture, chemicals and dirt, etc, to penetrate into the concrete to further worsen its porosity and weaken its durability.