Fire resistance of strain hardening cementitious composite with hybrid PVA and steel fibers

The novelty in this study was that, 0.5% volume of PVA fibers was replaced by steel fibers in strain hardening cementitious composite (SHCC) to alleviate the negative effect of melting of PVA fibers when exposed to fire. The resultant SHCC outperformed normal concrete specimens in terms of compressive strength reduction with elevated temperature. Compared to crushing failure of heated SHCC specimens with PVA fibers under compression, heated SHCC specimens with hybrid fibers exhibited a ductile failure mode. The tensile behavior of SHCC specimens heated to 300 °C did not show brittle rupture due to the addition of steel fibers. The addition of two types of fibers was also effective in preventing SHCC from explosive spalling at high temperature. This work provides a promising way to improve high-temperature mechanical properties of SHCC.