Fire resistance characteristics of materials with polymer gels which absorb aqueous solution of calcium chloride

It is well known that moist fire protection materials show good fire resistance characteristics. For this reason, these materials are usually made of mixtures of perlite-mortar and high-water-content materials such as silica gels or moist perlites. The latent heat of water plays an important role in the resistance of heat propagation in these materials. A superabsorbent polymer gel that absorbs calcium chloride solution contains much water, and it is one of these high-water-content materials. In this study, numerical simulations of fire resistance tests were conducted for materials of different mixing ratio of perlite-mortar and the super absorbent polymer gel to investigate the effect of the mixing ratio on the fire resistance characteristics. The effective thermal conductivity and the water content of the materials were measured and those values were used for computations. One of the test materials shows excellent fire resistance characteristics, and its fire resistance time at 60 mm thick is about 300 min. The relations of thermal properties and composition of the test material and the effects of mixing ratio of the gels and the perlite-mortar on the fire resistance characteristics are discussed.