Fire performance of pultruded wood-cored GFRP sandwich components for building construction

Abstract

Fire safety is significantly required for glass-fiber reinforced polymer (GFRP) sandwich composite structures since the GFRP skin and the core are normally sensitive to high temperatures. This study presents an investigation on the thermal responses, insulation performance, and charring behavior of the pultruded wood-cored GFRP sandwich (PWGS) components subjected to the ISO-834 fire. The PWGS specimens protected with calcium silica (CS) boards were exposed to one- or three-sides fire with the fire duration being 30 or 60 min. It was found that the GFRP skins without CS board protection were fully charred after the 30-min fire exposure. Nevertheless, the PWGS section exhibits good insulation. The average temperature rise of the unexposed surface of the PWGS sections without protection did not exceed 140 °C, satisfying the insulation requirement in specifications such as EN 1995-1-2, ASTM E119 and GB/T 9978.1. Further, the PWGS specimen with a 25 mm-thick CS board can survive without clear damage during the 60 min thee-sides fire exposure. In addition, the charring rate of the GFRP skin and the Douglas-fir core were summarized and discussed.