Herwani, Herwani, Iswandi Imran, Bambang Budiono, and Ediansjah Zulkifli. 2022. “Strength Enhancement, Ductility, and Confinement Effectiveness Index of Fly Ash-Based Geopolymer Concrete Square Columns ”. Journal of Engineering and Technological Sciences 54 (4):220411. https://doi.org/10.5614/j.eng.technol.sci.2022.54.4.11.