The construction industry is becoming aware of the existence of reinforcing bars made from fiber-reinforced plastic. Fiberglass rebar has been on the market for some time, making inroads where steel rebar doesn’t work well. The first common applications have been used in corrosive environments and places where the induced fields resulting from steel reinforced concrete structures exposed to high levels of radio frequency radiations are a problem. There is now a new entry into this field, rebar made from basalt continuous filaments.
Basalt is a common volcanic rock, found throughout the world where volcanoes have erupted and sent lava to the surface. It is actually present everywhere at a depth below the surface—there is a worldwide layer of basalt rock below the sedimentary or metamorphic rock that is exposed on the surface. Where it is present on the surface due to volcanic activity, it is available in large quantities. The shield volcano pictured in image 1 is in north-east New Mexico, and is about 20 miles long and 3,000 feet deep in basalt deposits, laid down from eruptions over millions of years.