A previous post on basalt rebar explained the use of basalt as an alternative to steel and fiberglass for reinforcing concrete. It’s a natural product made from basalt, a common, inexpensive volcanic rock. Basalt is also used to make fibers and roving for construction purposes. Fibers can be mixed with concrete and plaster for added strength. Roving looks like twine. The video below shows how a concrete dome is wrapped with roving. As shown in the video, this method saves on materials. The same process could be used on earthbag domes in seismic areas.
Details from Technobasalt, a supplier of basalt roving, basalt rebar, basalt fiber and other products:
“Basalt roving is bundle of continuous monodirectional complex basalt fibers. Roving possesses high natural strength, resistance to aggressive environments, long service life and excellent electric insulating properties. By its technical characteristics, Basalt roving surpasses S-glass and E-glass by many parameters, and is almost as good as carbon. Basalt roving is extremely heat resistant: long-use temperature range is 200-6800С. Temporarily it can work in up to 900 0С. Roving is extremely hard: 8-9 on the Moh scale (for comparison diamond=10). Its specific strength is 2.5 times higher than alloy steel’s and 1.3 times higher than E-glass.
– Lightness, high mechanical strength, corrosion and chemical resistance to alkali and other aggressive environments
– High frost resistance, heat resistance, moisture resistance
– Resistance to salty sea water
– Resistance to ultraviolet radiation