Fire resistance of square reinforced concrete column with one-face gypsum layer insulation under axial loading

Abstract

This study aims at investigating the fire resistance performance of square-reinforced concrete columns exposed to a standard hydrocarbon fire under a time-range axial loading. The gypsum layer is used as a prime fire protection for aggressive fire-flame. The gypsum boards are commonly employed as finishing material in construction. The ASTM C1529 hydrocarbon fire scenario is adopted in this study for all reinforced concrete samples subjected to axial load simultaneously exposed to direct fire flame of (600 and 900)oC. The experimental investigation is carried out on twelve laboratory-scale concrete samples. The outcome discussed the influence of various gypsum layer thicknesses applied to one face of the column sample under axial loading. The results showed different senses of fire resistance between samples. The gypsum protection layer reduces the effect of fire-exposed concrete specimens. For 1 h duration, 600 °C, and 10 mm and 20 mm gypsum layer thicknesses, the strength load evolution drops by 30.7% and 34.96%, respectively compared to the reference sample. Furthermore, for the 1-h duration, 900 °C, and 10 mm and 20 mm gypsum layer thicknesses, the load evolution drops by 29.6% and 34.58%, respectively compared to the reference model. Also, the strength drops by 15%, 19%, 29.4, and 17.9% for the same testing characterization, but a 2-h fire duration. The results show no spalling or delamination of the concrete substrate. Also, the amount of lateral deflection is improved.