Fire Resistance of Geopolymer Concretes

Geopolymer concrete has been proposed as an alternative to Portland cement concrete in applications requiring high degrees of fire resistance, because the intrinsic chemistry of the geopolymer binder does not require the retention of water or hydration within gel phases to maintain structural integrity of the binder. Portland cement concrete contains a high level of chemically bound water, which is essential to the gel binder structure, and which is lost upon heating to several hundred degrees Celsius, whereas the water present within a geopolymer concrete is overwhelmingly present in pores and is not an essential part of the strength-generating phases. However, predictions of geopolymer concrete fire performance have up to this time been based on small-scale laboratory testing (usually on paste or mortar specimens), rather than the study of large concrete sections, which provides significance to this work.