PROPERTIES OF BASALT FIBER REINFORCED GEOPOLYMER COMPOSITES

The properties, microstructure, and processing of potassium-based geopolymer (K2O center dot Al2O3 center dot 4SiO(2)center dot 11H(2)O) composites made with basalt chopped fibers have been systematically studied. Geopolymers were manufactured at ambient temperature and cured in a humidity controlled, constant temperature oven at 50 degrees C. The effects of varying weight percents of fibers, the presence of a polymer sizing, and processing methods were examined by comparing the strength and work of fracture of each sample with pure geopolymer. Basalt chopped fibers with a length of 1/4 inch increased the strength of a bend bar broken in a three point flexural test from an average of 1.7 MPa to an average of 19.5 MPa. Weibull statistics were analyzed and indicated a systematic and significant improvement in reliability due to the addition of chopped basalt fibers.