Concrete can be damaged by fire, aggregate expansion, sea water effects, bacterial corrosion, calcium leaching, physical damage and chemical damage (from carbonatation, chlorides, sulfates and distilled water).
This process adversely affects concrete exposed to these damaging stimuli.
However, precast concrete manufacturers are continually spending unnecessary amounts of time and money repairing defects often associated with the improper use of internal vibrators.
Therefore, to remove all trapped air and to consolidate concrete we recommend using a concrete vibrator.
Far less common are pop-outs caused by the presence of pyrite, an iron sulfide that generates expansion by forming iron oxide and ettringite. hydration of clay minerals in some aggregates, may lead to destructive expansion as well.Following the alkali-silica reaction (ASR), an expansive gel forms, that creates extensive cracks and damage on structural members.On the surface of concrete pavements the ASR can cause pop-outs, i.e.Like steel, these PVA fibers have high tensile strength and a greater modulus of elasticity than regular concrete.Unlike steel, PVA fibers develop a molecular and chemical bond with the cement during hydration and curing.