product description:
Polypropylene mono fiber is a high-strength bundled monofilament fiber made of polypropylene resin as the main raw material through a unique process. Adding it to concrete (or mortar) can effectively control micro-cracks caused by factors such as plastic shrinkage, settlement, and temperature changes of concrete (or mortar), and prevent and inhibit the formation and development of cracks. It can be widely used in industrial and civil construction, water conservancy engineering, road and bridge engineering, etc.
Enhancement function of polypropylene fiber to coagulation:
Anti-cracking effect on concrete:
The three-dimensional distribution of polypropylene mono fibers in concrete can effectively reduce the stress concentration at the tip of micro-cracks and prevent the occurrence and expansion of micro-cracks.
Improvement of concrete impermeability:
The uniform distribution of polypropylene mono fibers in concrete forms a supporting system, which reduces the bleeding of concrete and significantly improves the impermeability of concrete.
Experimental conditions:
According to the provisions of the national standard B/J82-85, the concrete mix ratio: cement: sand = 1: 1.7 water-cement ratio = 0.4
The test age is 28 days, after the initial water pressure is 0.1MPa, it increases by 0.1MPa every 8 hours until the maximum reaches 1.4MPa
Improve the freeze-thaw resistance of concrete:
The presence of polypropylene mono fibers can effectively reduce the concentration of tensile stress in concrete caused by multiple freeze-thaw cycles, prevent the further development of micro-cracks, and help improve its freeze-thaw resistance.
Experimental conditions:
Concrete mix ratio:
Cement: crushed stone: sand = 1:4:3 water-cement ratio = 0.6, the size of the test piece is 100x100x350mm, the age of the cylindrical shape is 28 days, the freezing temperature is -17 ± 1℃, the thawing is 8 ± 1℃, and a total of 300 times of freezing are carried out Melting cycle, each cycle is 4 hours.
Improvement of impact resistance and toughness of concrete:
Polypropylene mono fibers help to absorb the kinetic energy of concrete components when they are impacted, and due to the crack resistance effect of fibers, they can effectively enhance the impact resistance and toughness of concrete.
Experimental conditions:
Concrete mix ratio according to the national standard GB/T15231.5-94:
Cement:sand=1:2, water-cement ratio=0.38, specimen size: 120x50x10mmx6 pieces, age: 28 days
Improvements to concrete durability:
Due to the good crack resistance effect of polypropylene mono fiber, the occurrence and development of cracks are greatly reduced, the internal porosity is reduced, and the corrosion of the main reinforcement of the structure is reduced, so that the durability of concrete is greatly improved and enhanced.
Improvement of high temperature resistance of concrete:
In concrete, especially high-strength concrete, when polypropylene mono fibers are added, the uniformly distributed fiber monofilaments present a three-dimensional random distribution, forming a three-dimensional network structure. When the temperature inside the concrete member rises above 165℃, the fibers melt and form The internally connected channels allow the strong high-pressure steam to escape from the concrete, so it can effectively avoid bursting in a fire environment.
The use and construction process of polypropylene mono fiber:
1. Polypropylene mono fiber will not have any conflicts with concrete aggregates, admixtures, admixtures and cement, and there is no special requirement for mixing equipment.
2. Polypropylene mono fiber is easy to use. It is not necessary to change the original design ratio of concrete, nor to change the reinforcement ratio in the original design, nor to reduce the main stress reinforcement in the design at will.
3. Accurately weigh the fiber according to the designed dosage and concrete mixing volume. After preparing the sand and gravel, add the fiber and the aggregate to the mixer. The mixing time should be appropriately extended for 30-60 seconds. Random sampling after the mixing is completed, if the fibers have been evenly dispersed, the concrete can be put into use. If there are still bundled fibers, prolong the stirring time for 30 seconds, and then it can be used.
The construction and maintenance process of concrete with polypropylene mono fiber is exactly the same as that of ordinary concrete.
Post time: Jul-24-2023