Glass state continuous basalt fiber is time proven durable, sustainable, and environmentally friendly.
Despite their obvious color difference, golden brown continuous basalt fiber produced from naturally occurring volcanic basalt rock and man-made white silica fiberglass are chemically very similar blends of common quarry minerals. ACI (American Concrete Institute) recognizes FRP (fiber reinforced polymers) for use as concrete reinforcements. The June 2016 official printing of AC-454 now labels continuous basalt fiber and a special manmade fiberglass E-CR (corrosion resistant) fiberglass as sufficiently similar in overall performance as to be interchangeable for use in producing FRP concrete reinforcements. Brown basalt fiber reinforced polymer BFRP rebar and the white fiberglass GFRP rebar are now the only two “glass state” structural fibers officially recognized for concrete reinforcement.
Naturally, occurring basalt has several advantages.
As the single component required to produce continuous basalt fiber, the quarry process to collect basalt rock is inherently far smaller carbon footprint than mining a dozen minerals to produce man-made white silica based E-CR fiberglass.
In addition, basalt is opaque so it blocks the sun’s damaging ultraviolet rays naturally. Manmade white translucent fiberglass must be protected from UV light degradation.
At a base fiber level, the strength and durability glass state boron free basalt fiber enjoys over man assembled white fiberglass is the result of heat, pressure, and thousands of years of mixing mother nature put into the recipe to form the basalt rock.
Yes, manmade white E (electric) glass can be produced without the toxic mineral boron, its labeled E-CR (corrosion resistant). Basalt rock is naturally boron free and clearly basalt is time proven to remain “rock solid” standing today when all other minerals have long since eroded away.
(photo basalt columns)
In a “glass state,” both basalt and silicate glass are inorganic materials. During fiber production both receive a “size” coating(s) generically called a “sizing” process.
This coating is something less than 100 μm (stands for “micrometer” also called a “micron” which is one-millionths of a meter or 0.000039 of an inch). This ultra-thin coat of “size” preforms to protect the fiber as it acts as the coupling agent to provide the load linkage to glass state fibers at a molecular level called a “covalent bond”. Not only does “size” become part of the fiber to seal and protect, the sizing process also extends a molecular chain with a dispersant to which organic resin such as epoxy resin will crosslink there by further to seal off and enhancing durability against fiber damage from the environment for hundreds of years.
Clearly, compared to rusty steel modern Fiber Reinforced Polymers are a paradigm shift enhancement to the reinforcement of our concrete infrastructure.