Experimental investigation and statistical analysis on structural design and impact strengths of fiber geopolymer mortar

Due to the high consumption of mortar and concrete, especially in structures and the increasing demand for cement production, considering the environmental degradation effects of this substance, it seems necessary. One of the solutions is to produce environmentally friendly materials and reduce the damaging effects of Portland cement production, Such as slag geopolymer mortar and concrete. The purpose of this paper is to experimentally investigate the statistical approach of the mechanical and resistive properties of cement mortar and geopolymer fibers mortar. Four mix design including three geopolymer mix design with 0, 0.5, and 1% steel micro-fibers and a conventional mortar mix design were considered. A total of 320 specimens were made, each consisting of 20 cubic specimens, 20 cylindrical specimens, 20 small beam specimens, and 20 small disc specimens. The results indicated that by increasing the percentage of steel microfibers up to 1% in geopolymer samples, the compressive strength, tensile strength and modulus of rupture increased by 6.39, 60.86, and 63.40%, respectively. The number of destruction resistance blows was also about 25 times higher. In all compressive, tensile, flexural, and impact strengths tests, the non-fiber geopolymer specimens had better behavior than conventional cement mortar specimens. In all geopolymer specimens with increasing fiber percentage, standard deviation and coefficient of variation increased as a result of data dispersion.