Analisis Kondisi Beton Campuran Serat Polypropylene (KRATOS MACRO PP54+) Pada Efek Peningkatan Suhu Thermal awal

Fire is a disaster that significantly impacts building structures, with cases steadily increasing each year in Indonesia. Exposure to high temperatures causes damage to structural elements, including a reduction in compressive strength. This study analyzes the performance of concrete mixed with polypropylene fibers (Kratos Macro PP54+) under initial thermal temperatures based on ISO 834 standards, starting from 200°C. The study aims to examine the effect of increasing initial thermal temperature on the mechanical properties of concrete mixed with polypropylene fibers. Fiber-reinforced concrete was tested at temperatures of 90°C, 150°C, and 210°C with heating durations of 2, 4, and 6 hours to observe changes in compressive strength, splitting tensile strength, and flexural strength due to heat exposure. The tested concrete had a strength of 20 MPa with the addition of 0.2% polypropylene fibers by total volume weight. After heating, samples were tested under natural cooling and water immersion cooling conditions. Results showed the most optimal condition at 90°C heating for 2 and 4 hours, where compressive strength increased by 41.73% and splitting tensile strength improved by 36.04% compared to normal temperature. Concrete cooled naturally showed better strength than those cooled by immersion. This study supports the use of fiber-reinforced concrete as an alternative material for structures exposed to high heat, such as fire-resistant buildings. The research is expected to serve as a reference for the development of fire-resistant structural concrete.