Chemical resistance and toughness of fiber-reinforced ferrocement composites in H2SO4 and Na2SO4 environments: Enhancing the flexibility of structural foam concrete

Abstract

This study investigates the chemical resistance, toughness, and flexibility of fiber-reinforced ferrocement composites exposed to H2SO4 and Na2SO4 environments. Glass fiber (GF), polypropylene fiber (PPF), and polyvinyl alcohol fiber (PVAF) were incorporated to enhance durability. Metakaolin (MK) and micronized waste marble powder (WMP) were used as supplementary cementitious and filler materials, respectively, while a foaming agent was introduced to reduce unit weight. PVAF-reinforced composites demonstrated superior performance in all tested conditions. The lowest water absorption (5.1 %) and highest compressive strength (58.4 MPa at 28 days and 62.7 MPa at 91 days) were observed in PVAF composites. Under Na2SO4 exposure, PVAF composites retained 85 % of their compressive strength with only 2.6 % mass loss, while under H2SO4 exposure, 76 % strength retention and 5.1 % mass loss were recorded. Structural efficiency and flexural toughness were also maximized in PVAF composites. SEM analysis confirmed a denser, more compact microstructure with reduced porosity in fiber reinforced samples, further validating their improved durability. These findings suggest that PVAF-reinforced ferrocement composites are a viable alternative for structural applications in chemically aggressive environments, offering improved mechanical performance and chemical resistance while reducing material weight.