Polypropylene fiber concrete which can be added to achieve the effect of crack about 80% (I used to paint the mortar, delivery and acceptance, see the end of the appearance of cracks, or to cracks in the past few years, but better than without polypropylene fibers The much better). Quality polypropylene fiber is the key (in water dispersion, the country did not import the fiber is good in the water cabbage useless!) But there is no effect of structural cracks. A slight decrease in compressive strength. Much of the domestic manufacturers, contact with a number, because the price difference is too large! Do not nailed one. The main role of fiber in fiber concrete, is to limit the expansion of the external force cement binder cracks. In Loaded (pulling, bending) early, cement-based materials and fibers together to withstand external forces, while the former is the main bearer of force; when the base cracking, cracks across the fiber to become a major force bearer. If the fiber volume fraction is greater than a critical value, the entire composite material can withstand higher loads and continue to have a greater deformation until the fiber or fibers being pulled off aside from the binder, so that the composite material damage. Compared with ordinary concrete, fiber reinforced concrete with high tensile and flexural ultimate strength, toughness level of increase is especially large. Polypropylene fibers in concrete There are two main purposes: 1) to prevent the concrete plastic shrinkage cracks. In the process of setting and hardening of concrete, the surface can cause dehydration and plastic shrinkage cracks, concrete mixing polypropylene fibers, can prevent such cracks. Since the elastic modulus polypropylene fiber is less than the hardened concrete, so hardened concrete to crack resistance (temperature stress or mechanical loads such as the role cracks) increase limited against pulling, bending strength increase is not large, concrete toughness increase to a certain extent. 2) improve the fire resistance of hardened concrete. Under high temperature, the polypropylene fibers will soften and burned, many pores are formed in the concrete, the concrete is high-temperature water can be vaporized along the discharge channels, to prevent vaporization of water to form an internal high pressure burst leaving concrete, thereby greatly improve the fire resistance of concrete and fire rating. These are our best promise manufacturers of market research concluded there to tell you at the time of purchase we have to understand clearly go buy quality purposes.