civil engineering. Basalt rock fiber $($BRF$)$ is a type of reinforcing fiber that is derived from basalt rocks. Basalt fibers are produced by melting basalt rocks at high temperatures and then converting the molten material into fibers. Basalt is an igneous rock that is formed from the solidification of lava or magma.

BRF has gained attention in civil engineering projects due to its excellent mechanical properties and durability. Here are some key characteristics and applications of basalt rock fiber:

$1.$ Strength and Durability: Basalt fibers have high tensile strength and are resistant to corrosion, chemicals, and UV radiation. They exhibit better tensile strength and modulus compared to traditional reinforcing materials like steel.

$2.$ Lightweight: BRF is lightweight, which makes it easier to handle and transport. This characteristic is beneficial in reducing the overall weight of structures and improving construction efficiency.

$3.$ Thermal Stability: Basalt fibers have good thermal stability and can withstand high temperatures. This property makes them suitable for applications where exposure to heat or fire is a concern.

$4.$ Sound and Heat Insulation: Basalt fibers have excellent sound and heat insulation properties. They can effectively reduce noise transmission and provide thermal insulation in buildings.

$5.$ Environmental Sustainability: Basalt rock is a naturally occurring material, and the production of basalt fibers requires less energy compared to other reinforcing fibers. Additionally, basalt fibers are non$-$toxic and recyclable, making them an environmentally friendly choice.

Applications of Basalt Rock Fiber in Civil Engineering:

$-$ Reinforcement in Concrete: BRF can be used as a reinforcement material in concrete structures, such as beams, columns, and slabs. It enhances the strength, crack resistance, and durability of concrete.

$-$ Geotechnical Engineering: Basalt fibers can be used in soil stabilization, slope reinforcement, and erosion control applications. They improve the stability and load$-$bearing capacity of soil.

$-$ Bridge Construction: BRF can be utilized in the construction of bridge decks, bridge girders, and other bridge components to enhance their structural performance and increase their service life.

$-$ Retrofitting and Repair: Basalt fibers can be used for retrofitting and repairing existing structures to improve their structural integrity and extend their lifespan.

Question: Basalt rock fiber is derived from which type of rock? A$)$ Sedimentary rock B$)$ Igneous rock C$)$ Metamorphic rock D$)$ Volcanic rock