Problems with fresh concrete

The cause of long-term damaging of concrete are three key factors, which operate during the initial phase, when the liquid concrete is hardening:

1. Plastic contraction and setting:

    a) Plastic contraction causes cracks, when the fresh concrete is subjected to excessive premature drying of the surface due to climatic conditions or due to absorption of water into the underlay.  After fast contraction of the concrete volume, direct or diverse cracks form. In case of such contraction, the fibre PP 12/18 can reduce the risk of spreading such crack.

    b) Plastic setting of concrete can lead to cracks along inserted reinforcements. Under the reinforcing ribs there are often voids. Such defects of concrete can be strongly lowered by adding polypropylene fibres. The fibre FIBRIBET® reduces the risk of crack formation during the early phase of concrete setting. The fibres ensure controllable hydrating and thus lower the risk of concrete perspiration. Hardening of concrete improves and the risk of crack formation is reduced consequently.

2. Erosion of sand grains

Damage occurs in the surface layer of concrete. Individual fractions of the aggregate separate, when the concrete is mixed. So the gross fraction remains at the bottom and fine fraction ends up on the surface. By application of the polypropylene fibres this effect can be avoided.

3. Damage due to frost

In case of unprotected surfaces, water can get into the concrete through small voids and capillaries. Frost causes water to expand and tear concrete apart. Subsequent damage leads to erosion, flaking off and loosening of concrete. Laboratory tests and the realised concrete surfaces show, that using of polypropylene fibres increases concrete resistance to frost. The fibres FIBRIBET ® lead to results that are comparable with frost-proof concrete.