The effects of synthetic wollastonite microfibers on the properties of engineered geopolymer composites developed with different design and curing parameters

Synthetic wollastonite microfibers (SWMs) with the codes SWM-I and SWM-II were generated in the first step of this thesis, which was completed in four stages. While SWM-I was produced using natural resources, SWM-II was chosen from the SWMs developed with different waste materials and design criteria. In the second stage, an attempt was made to improve an engineered geopolymer composite (EGC) with ''bearing strength and deformation capacity'' similar to that of the engineered cementitious composite (M45-ECC), which is known with the standard M45 code. For this purpose, fly ash (FA) and fly ash+slag (FA+S)-based EGCs have been evolved with different design and curing parameters. EGCs were designed with fresh and rheological properties similar to M45-ECC. In addition, the mechanical and microstructural properties of M45-ECC and EGCs were investigated. A FA+S-based EGC mixture was selected from the developed FA/FA+S-based EGC mixes. In the third stage, SWM-I and SWM-II wollastonites were used in the ratios of 3%, 6% and 9% instead of FA. The mechanical tests and microstructural analyzes indicated that SWM-I mineral improved more effectively the performance of FA+S-based EGCs. Therefore, in the fourth and final stage, the permeability, durability and dimensional stability properties of FA+S-based EGCs incorporating SWM-I and M45-ECC were investigated. According to the results, 6% SWM-I was determined as the optimum ratio for design.