In the last years , The use of polymer-reinforced composites as high-performance materials in concrete structures has expanded significantly. FRP composite is famous for its features such as high strength, Lightness and wear resistance.
However , Different types of this product show different aspects of resistance and elasticity. In this article we will talk about the production and use of FRP, its types and benefits.
Reinforced polymer composite
During this decade, The control and analysis of concrete and steel structures has attracted much attention, Not only because of the short life of the structure but also regarding safety issues. Although concrete structures generally show a good level of resistance, However, severe earthquakes, Besides corrosion of concrete structures, Sometimes it led to serious damage.
for this reason , It is proposed to use more reliable alternatives or strengthen these structures with auxiliary materials for a long period, It tests many cases of new materials. One such case is reinforced polymer composite or FRP.
Tests FRP reinforced concrete columns and beams in various conditions for use as replacements in structures.
The use of FRP in the form of longitudinal and transverse reinforcements is currently practically available in buildings and bridges. The reason for using this material is its excellent performance and special resistance to corrosion.
compared to steel, The reinforced polymer composite features high strength-to-weight ratio and good flexibility, Which makes it a suitable alternative in many structures.
Investigation of the effects of FRP on the behavior of reinforced concrete
In order to investigate the effect of FRP on the shape and structure of the structure and to strengthen its flexibility, We studied its use in columns and beams. The effect of the polymer-reinforced compound on the work of columns and beams is studied in various experiments.
Columns and beams strengthened by FRP showed adequate strength and flexibility in structures and against earthquakes. Tests conducted under reverse rotation load showed that the drift capacity of columns and beams is more than 3%. FRP beams also showed good ability to withstand pressure.
The effect of using FRP materials on reinforced concrete columns
Sufficient power: Using FRP in columns or beams, While maintaining the weight at an appropriate level, It also achieves sufficient strength.
Low wear: We said that one of the issues with the steel used in the structure is corrosion. One of the best features of FRPs is good corrosion resistance.
Ease of transportation: in general , FRP does not have a high weight due to its components, Hence, it is easy to transport.
Better look and feel: Due to the cube-like shape and appearance of FRP and FRP reinforced concrete, The appearance of columns and beams made of it in the skeleton is better.
Long service life: Due to corrosion resistance, The service life of reinforced concrete increases when using FRP.
Effects of FRP on the behavior of reinforced concrete columns
Using FRP in concrete can increase its resistance to compression. In this case , due to imprisonment, FRP fibers are stretched transversely along the shaft and play the shape of the spine.
In reality , FRP works in this case only if the stress on the concrete reaches a maximum point. In this way the resistance is greatly increased. naturally , The strength of concrete in this method depends largely on the amount of FRP fibers used.
Effect of different fibers used in FRP
Fiber glass: Fiberglass is one of the most popular materials for FRPs due to its low price, high tensile strength (flexibility), and high thermal elasticity. The electrical resistance of fiberglass makes it useful in terms of fire safety in critical situations.
carbon fibre: Due to its high tensile strength, Carbon fiber increases the strength and flexibility of reinforced concrete under pressure.
Disadvantages of reinforced polymer composite
- High cost: Some composite materials in the production of some FRP composites impose a high cost on the structure.
- Heat intolerance: Some FRP fibers such as carbon and aramid have low heat resistance.
FRP use cases
- Improve endurance: Reinforced polymer composite is used most of the time as an auxiliary frame and to increase the load-bearing capacity of the structure.
- Change and modification: Fiber reinforced composites are used to replace and modify damaged or weak points.
conclusion
Increasing the resistance of various structures against earthquakes has been a major concern for all ages of human settlements. The use of concrete structures has shown its efficiency to a great extent against these unforeseen events.
However , Concrete structures corrode after some time and actually have a limited lifespan, On the other hand , In some specific places, The use of concrete structures has not achieved complete safety. For this reason and with advances in technology, Efforts are being made to come up with an effective new product.
at the same time , FRP with fiber reinforced polymer materials is one method that has been strongly proposed in the past decade. naturally , Note that the reinforced polymer composite, Despite its high positive characteristics, It is still far from reaching the point of 100% safety.