Basalt Fiber Reinforcement in Practical Engineering Applications and Research
1.Basalt fiber reinforcement in concrete pavements
Continuously reinforced concrete pavements control cracking due to shrinkage by placing a sufficient number of reinforcement bars in the longitudinal direction. This design not only enhances the loading capacity and durability of the highway but also improves the driving environment for automobiles by not providing expansion and contraction joints during construction. However, since the pavement structure cannot be completely closed, factors such as rainwater infiltration and frost heave can lead to corrosion of the steel reinforcement, which seriously affects the service life of the highway.
Basalt fiber reinforcement can be used in place of traditional steel reinforcement for continuously reinforced concrete pavements due to its excellent corrosion resistance and high tensile strength. This alternative solution effectively solves the problem of steel corrosion, thus significantly improving the durability of concrete pavement. In addition, basalt fiber reinforcement belongs to low-carbon and environmentally friendly materials, and its price advantage will become more and more prominent with the depletion of iron ore resources. Existing studies have shown that applying BF-RP reinforcement in concrete pavements shows obvious benefits in terms of durability and corrosion resistance, and the construction difficulty and progress are comparable to that of steel reinforcement. However, due to the relatively low modulus of elasticity of BF-RP reinforcement, it is necessary to slightly increase its reinforcement ratio, usually between 0.78% and 1.0%, and to adopt the design concept of “small reinforcement diameter and close spacing”.
2.Research on basalt fiber reinforcement in reinforcing short concrete eccentric compression columns
Traditional reinforcement methods usually use outsourced steel, but this method is cumbersome in construction and has poor resistance to high temperature and corrosion. The lightweight, high-strength, high-temperature and corrosion-resistant properties of basalt fiber materials bring a new choice for the reinforcement process. At present, the reinforcement technology of bonded basalt fiber sheets is mature, but the research on improving the flexural load capacity of concrete columns by embedding basalt fiber tendons is relatively small. Relevant literature shows that basalt fiber reinforcement significantly improves the lateral bending capacity of concrete columns and can further enhance the load carrying capacity by combining the method of outsourcing basalt fiber cloth.
The construction sequence of embedded basalt fiber reinforcement is as follows:
- Open the groove according to the design size
- Wash the groove
- Apply bonding agent (epoxy resin adhesive)
- Embedding BF-RP bars
- Fill with binder evenly
- Wait for the binder to cure and then carry out surface treatment.
By combining with the outsourced basalt fiber cloth, the BF-RP reinforcement can effectively avoid the phenomenon of slipping and spalling in the process of stress, the construction is convenient and efficient, and occupies less space, which has unparalleled advantages.
3.Basalt fiber reinforced concrete beams
BF-RP reinforcement is an environmentally friendly, high-strength non-metallic reinforcement material that possesses properties such as corrosion resistance, electromagnetic insulation, and fatigue resistance, making it a preferred alternative to steel reinforcement in certain special projects. However, unlike conventional steel bars, BF-RP bars do not have a significant yield point and have a low modulus of elasticity, which may result in greater deflection of concrete beams subjected to the same load. Although the damage of concrete with BF-RP reinforcement is brittle and has no obvious prognosis, it produces large deformation before damage, which instead provides a warning for structural safety.
If the building has more stringent requirements for concrete cracking, it is necessary to consider applying prestressing to the basalt fiber tendons, or increasing their modulus of elasticity, and mixing and matching them with steel reinforcement to ensure the stability and safety of the structure.
