Polypropylene fiber applications in some common problems, are summarized as follows:

A polypropylene fiber can used as a waterproofing material it?
    Waterproof concrete structure principle, there are three:
    An expansion compensated;
    2, less dense water;
    3, crack waterproof.

    And this is through physical polypropylene fiber reinforced concrete action to reduce cracking, avoiding the formation of pores through which greatly enhance the ability of concrete waterproofing, concrete structural rigidity self waterproof ideal material.
Second, the incorporation of polypropylene fiber concrete in what role?
   1) reduce shrinkage cracks of concrete, improve impermeability and durability of concrete.
2) ensure the homogeneity of the concrete.
3) reduce the brittleness of concrete.
4) improve the fire resistance of concrete.
Third, whether to use a special concrete mixer for mixing the fibers? Can adding fiber in concrete?
    No special equipment. Commonly used on construction sites compulsory concrete mixer to prepare fiber reinforced concrete. In order to ensure uniform mixing fiber in concrete, time may be extended. One approach is to press conventional concrete mix is ​​made, then in the case of non-stop, and would have been weighed fiber added concrete, continued to stir 3mins, the fiber becomes a root of monofilament evenly distributed in the concrete mixing feed. In more practical engineering methods used, directly to the fiber material and gravel into blender together, the better.
In the concrete mixing station can be prepared FIBER concrete products. May impose artificially feed mixing equipment from the charging port on the platform directly into weighed fibers. Although the density of the fibers is only 0.91g / m3, but the actual operation showed no flying phenomenon when feeding. Adding a slight decrease in fiber concrete slump, but does not affect the work of concrete, concrete slump does not affect change over time (time-dependent change of concrete slump mainly depends on the water reducer) .
Fourth, the appropriate content of polypropylene fiber in concrete is how much?
Polypropylene fiber can play its role in the concrete, to a large extent depend on the number of single fibers and evenly distributed in the concrete. Since the surface of the coated fibers have a special coating, can be very evenly distributed in the concrete tens of millions of filaments. For this reason, in general, fiber content in concrete does not have to be too high, 1m3 in adding 0.6-1.2kg can. Set to take the fiber content is added 0.9㎏ 1m3 concrete, concrete 1m3 in volume monofilament fiber (length specification 12mm) of nearly 200 million can be achieved.
Fifth, polypropylene fibers and expansive effect What's the difference?
Mixed with bulking agents and adding fiber in concrete seepage can achieve the purpose of cracking. But the role and effectiveness of the principle there are some differences.
1) Principle: expanders generated by the chemical reaction of ettringite or calcium hydroxide crystals, the concrete expands to compensate for the contraction, thereby reducing or preventing the generation of concrete cracks. Fiber through physical action to reduce
Cracks in concrete production.
2) Effect: expanders only in wet conditions in order to obtain good crack seepage effect. If in a dry environment, it may not be effective or even counterproductive; and fiber, whether wet or dry environment can get a good crack seepage effect.
3) Construction conditions: bulking agent for curing conditions are very harsh, requiring water conservation more than 14 days, no special requirements on the conservation of fiber.
Six, polypropylene fibers in the mixing process will not be into the group?
Will not. Through a special process of the fibers during the mixing process, by mechanical stirring, aggregate impact, in the alkaline environment of the cement slurry can be automatically dispersed, uniformly distributed in three dimensions, does not agglomerate.
Seven, with the need to change the use of polypropylene fiber concrete or mortar than it?
Required. Polypropylene fiber is a complete physical reinforcement effect, concrete mix without adjustment.
Eight, polypropylene fiber can reduce concrete cracking it?
Fiber can effectively reduce the plasticity of concrete cracking and drying shrinkage cracking early, experimental results show that the fibers can be reduced by more than 90% of this cracking.
Nine, polypropylene fibers what precautions it?
Note:

1, the role of fiber is a "secondary reinforcing ribs" irreplaceable structural reinforcement material, and do not reduce the size of the main structure.

2, can not be used alone to solve the settlement, massive concrete hydration heat and strong external shocks occasions.

3, can not be reduced because of the use of fiber construction quality management requirements, shall continue to be relevant national technical specifications for construction and maintenance.