"Considering that fibreglass also increases mechanical strength, this is an important factor in FC’s stability... High-strength foamed concrete is obtained by introducing (PP) fibre into the raw mix... Many of the currently used fibres have been investigated, including PP... blend of polypropylene with glass... ... ... steel... palm oil, coconut... and other fibres... introduced in an amount of 0.2–1.5% volume of the concrete mixture; however, in this article, the fibre content ranges upper limit has been extended to 5%. As an alternative to traditional reinforcement, one strategy with composite mesh and mesh combined with fibre has also been studied for lightweight foamed concrete (LWFC)..."
January 1, 1970
https://en.wikiquote.org/wiki/Foam_concrete