"béton armé" or "béton fibré" refer to the inside of the concret. "Béton_brut" referes tothe surface A concrete building can be both "brut" and "armé" at the

"béton armé" or "béton fibré" refer to the inside of the concret. "Béton_brut" referes tothe surface A concrete building can be both "brut" and "armé" at the same time. https://en.wikipedia.org/wiki/B%C3%A9ton_brut https://en.wikipedia.org/wiki/B%C3%A9ton_brut