Gerhard Botha, local reseller Penetron South Africa civil engineer and technical manager says a chemical additive causes impermeable crystals to grow inside the concrete and seal cracks, pores and capillaries, preventing liquids from penetrating the concrete.
This nontoxic additive can be used to seal concrete structures in potable water systems and in more aggressive applications, such as sewage treatment and mining processing applications.
The Green Building Council five-star green-rated Penetron Admix is added to concrete at the time of batching, while Penetron Slurry is applied to existing structurally sound concrete surfaces, and increases the concrete’s compressive strength by 7 percent to 10 percent.
Penetron consists of Portland cement, fine treated silica sand and various active and proprietary chemicals.
Botha adds that when applied to a concrete surface, the active silica components react with moisture and calcium hydroxide to form an insoluble silica crystalline structure.
These crystals have been proven to grow against 160 m of hydrostatic pressure into the pores, capillaries and minor shrinkage cracks in the concrete, which prevent any liquid ingress.
