The durability of concrete to freeze and thaw (F-T) cycles is one of the most important challenges of reinforced concrete structures in regions with cold climate. Thus, studying the effect of this phenomenon on concrete properties to evaluate the vulnerability rate of these structures during frequent F-T cycles seems necessary. The use of nanomaterials in cement-based composites leads to many improvements in concrete properties due to their small particle size and large specific surface area. In this paper, the fabricated self-compacting concrete (SCC) specimens containing different portions of nano-clay (NC) and mineral admixtures including silica fume (SF), fly ash (FA), rice husk ash (RHA) and ground granulated blast furnace slag (GGBFS) were subjected to F-T cycles in the temperature range of −18 to +4 °C according to ASTM C666-A standard specifications. The properties of specimens including the mass, electrical resistivity, dynamic modulus of elasticity and compressive strength were measured during the F-T cycles. Results showed that using 3% NC considerably improves the F-T resistance of SCC, as compared to the control mix. Also, improvements were observed on the frost resistance of SCC containing mineral admixtures by the addition of 3% NC to the mix proportions.

The increasing global emphasis on sustainable construction practices has spurred significant international research into developing durable and eco-friendly concrete materials. This study investigates the potential of metakaolin and glass powder as supplementary aluminosilicate materials in slag- based geopolymer mortars, aiming to enhance their mechanical properties and durability. To further improve the performance, polypropylene fibers were incorporated at various dosages. Therefore, 13 mixtures of geopolymer mortar based on blast furnace slag have been developed. The control mix does not contain fibers or slag replacement materials, whereas in the other formulations, glass powder and metakaolin have been employed as substitutes for slag at weight percentages (relative to the weight of slag) of 5% and 10%, separately and in combination. Additionally, the fiber-containing samples are divided into two groups based on the volume percentage of polypropylene fibers, comprising 0.2% and 0.4%. The results of the investigation show that the use of glass powder, particularly at a replacement percentage of 10%, leads to an improvement in the 28-day compressive strength. Furthermore, the mixes containing glass powder demonstrated higher flexural strength compared to those containing metakaolin, irrespective of the volume percentage of fibers. The best performance in the rapid chloride permeability test is associated with the mix containing a combination of glass powder and metakaolin at a replacement percentage of 10%. Satisfactory results have been obtained when using fibers at volume percentages of 0.2% and 0.4%. Additionally, this study utilized a fuzzy inference system to predict compressive strength. The results indicate that, by considering uncertainties, the compressive strength of the mortar can be predicted with an error of less than 1% without the need for complex mathematical calculations.