Workability, compressive strength, and efflorescence characteristics of one-part mix alkali-activated circulating fluidised bed combustion fly ash-based mortars
Jason Shun Fui Pei,
Chung Siung Choo,
Deni Shidqi Khaerudini,
Sing Muk Ng,
Dominic Ek Leong Ong,
Melvina Tan,
Jaka Sunarso
Affiliations
Jason Shun Fui Pei
Faculty of Engineering, Computing and Science, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia; Research Centre for Sustainable Technologies, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia; Research Centre for Innovative Society, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia
Chung Siung Choo
Faculty of Engineering, Computing and Science, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia; Research Centre for Sustainable Technologies, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia; Research Centre for Innovative Society, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia; Corresponding authors.
Deni Shidqi Khaerudini
Research Center for Advanced Materials, National Research and Innovation Agency, Bld. 440 Kawasan Puspiptek Serpong, Indonesia
Sing Muk Ng
Research and Development Department, Sarawak Energy Berhad, No. 1 The Isthmus, 93050 Kuching, Sarawak, Malaysia
Dominic Ek Leong Ong
School of Engineering and Built Environment, Griffith University, Nathan, Queensland 4111, Australia
Melvina Tan
Research and Development Department, Sarawak Energy Berhad, No. 1 The Isthmus, 93050 Kuching, Sarawak, Malaysia
Jaka Sunarso
Faculty of Engineering, Computing and Science, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia; Research Centre for Sustainable Technologies, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia; Research Centre for Innovative Society, Swinburne University of Technology, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia; Corresponding authors.
In this study, one-part alkali-activated mortars are formulated using circulating fluidised bed combustion (CFBC) fly ash, derived from lignite (brown coal) combustion, as the precursor, and sodium hydroxide (NaOH) and sodium metasilicate (Na2SiO3) as the solid activators. Experimental findings indicate that an increase in solid activator-to-precursor ratio correlates with improved workability and compressive strength of the mortars. The influence of Na2SiO3-to-NaOH ratio on the compressive strength of the mortars is apparent only in mixes with a high solid activator-to-precursor ratio of 0.4 and 0.5, indicating its relatively lesser significance compared to the solid activator-to-precursor ratio. The mechanism through which an increase in the solid activator-to-precursor ratio improves the compressive strength of the mortars is elucidated using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The results indicate that increasing the solid activator-to-precursor ratio enhances the degree of alkali-activation for fly ash, thereby improving the compressive strength with increasing solid activator-to-precursor ratio.
