Basalt is a volcanic rock that can be melted and spun into fine fibers that have high strength, corrosion resistance, thermal stability and durability. These fibers can be chopped into short strands and mixed with cement mortar to create a reinforced composite material that has many advantages over conventional concrete.
In this blog post, we will explore the application of chopped basalt fiber strands (CBFS) in real construction projects in China, where basalt is abundant and cheap. We will also discuss the benefits and challenges of using CBFS in different types of structures and environments.
What are the benefits of using CBFS in construction?
CBFS can improve the fresh, mechanical, durability and dynamic properties of mortar. Some of the benefits are:
- CBFS can reduce the surface cracks, shrinkage and stress concentration in massive concrete structures.
- CBFS can increase the toughness, impact resistance, tensile strength and flexural strength of mortar.
- CBFS can enhance the bond strength between old and new substrates, which is important for repair and retrofitting projects.
- CBFS can improve the fracture toughness and post-cracking behavior of mortar by bridging the cracks.
- CBFS can improve the abrasion resistance, freeze-thaw resistance, chemical resistance and fire resistance of mortar.
- CBFS can reduce the weight and cost of concrete structures by replacing steel reinforcement or reducing cement content.
What are the challenges of using CBFS in construction?
Despite the many benefits of CBFS, there are also some challenges that need to be addressed before they can be widely adopted in construction projects. Some of the challenges are:
- The optimal dosage, length and diameter of CBFS for different mortar mixes need to be determined by experimental studies and design guidelines.
- The compatibility and dispersion of CBFS with different types of cement, admixtures and aggregates need to be ensured by proper mixing methods and quality control.
- The durability and long-term performance of CBFS-reinforced mortar under various environmental conditions need to be evaluated by accelerated aging tests and field observations.
- The health and safety risks of handling and inhaling CBFS need to be assessed and mitigated by appropriate protective measures and regulations.
How are CBFS used in real construction projects in China?
China is one of the leading countries in producing and using basalt fibers for various applications, including construction.some of the real construction projects that have used CBFS are:
- The Shanghai World Financial Center, where CBFS were used to reinforce the concrete slabs and columns for fire protection and seismic resistance.
- The Beijing Olympic Stadium (Bird’s Nest), where CBFS were used to reinforce the concrete roof for structural stability and aesthetic effect.
- The Hangzhou Bay Bridge, where CBFS were used to reinforce the concrete deck for durability and fatigue resistance.
- The Nanjing Yangtze River Bridge, where CBFS were used to repair the cracks and spalling of the concrete piers for extending service life.
- The Guangzhou Metro Line 3, where CBFS were used to reinforce the tunnel lining for reducing water leakage and improving safety.
Conclusion
CBFS are a promising material for reinforcing cement mortar for various construction projects. They have many advantages over conventional concrete in terms of strength, durability, cost and environmental impact. However, they also face some challenges in terms of optimal design, compatibility, performance and safety. More research and development are needed to overcome these challenges and promote the wider use of CBFS in construction industry.
