1. Effectively improves the crack resistance of concrete (mortar)
In construction practice, polypropylene fibres have become an extremely effective means of improving the crack resistance of mortar and concrete. They are surface-treated using a special production process and have extremely strong adhesion to cementitious materials, so they can play a more effective crack-resistant role in concrete. Studies by relevant institutions have shown that the random distribution of polypropylene fibres in concrete greatly helps to reduce the effects of plastic shrinkage and stress caused by freezing and thawing. The energy from shrinkage is dispersed among tens of millions of filaments per cubic metre, each with high tensile strength and relatively low elastic modulus. This greatly enhances the toughness of the concrete (mortar) and inhibits the formation and development of micro-cracks.
At the same time, the chaotic support system formed by countless fibrous filaments inside the concrete can effectively prevent the segregation of aggregates, ensure uniform bleeding of water in the early stage of concrete, and thus prevent the formation of settlement cracks.
2. Greatly improve the impermeability and waterproofing properties of concrete (mortar)
Adding an appropriate amount of microfibers to concrete can effectively inhibit the generation and development of early drying shrinkage microcracks and segregation cracks, greatly reducing the amount of concrete shrinkage, and in particular, effectively inhibiting the generation of connected cracks. The large number of fibers evenly distributed in the concrete and adhering to each other act as a ‘support’ for the aggregate, reducing the segregation of the aggregate and the water separation on the surface of the concrete, thereby greatly reducing the pore content in the concrete and greatly improving the impermeability.
The use of polypropylene fibres as a rigid self-protection material in concrete basement projects, roofs, water tanks, external wall plastering, etc., is particularly effective and can effectively solve the problem of seepage and cracking.
3. Enhances impact resistance
After the fibres are added to the concrete and set, the high-strength fibrous strands that hold the cement together become a dense randomly distributed mesh reinforcement system, which is beneficial for preventing and controlling the formation and development of micro-cracks and enhancing the toughness of the concrete.
At the same time, it effectively improves bleeding, which is very helpful for early curing. The unique surface treatment process of the fibres allows them to bond closely with the cementitious material. The hydration reaction of the cement is more complete, aggregate segregation is reduced, and the grading is more uniform. This greatly maintains the overall strength of the concrete. When the concrete is impacted, the fibres absorb a large amount of energy, thereby effectively reducing the effect of concentrated stress, hindering the rapid expansion of cracks in the concrete, and enhancing the impact resistance of the concrete.
4. Enhanced frost resistance
Adding polypropylene fibres to concrete can relieve the effect of internal stress caused by temperature changes and prevent the expansion of micro-cracks. At the same time, the improvement of the concrete’s impermeability also helps to improve its frost resistance.
The use of polypropylene fibre concrete in public buildings and facilities in cold regions has effectively reduced the problem of frost heaving. It can be used as an effective means of compensating for temperature differences in concrete.
