Tests and finite element modeling of circular geopolymer compressive members with lateral FRP spiral wrapping

These days, cement production is increasing due to the growing world population, leading to expanded use of concrete in buildings. Yet, the production of cement significantly increases carbon emissions, putting the future of sustainable development at risk. Geopolymers are under research for their potential to reduce the impact on concrete buildings. In order to tackle this issue, the literature has yet to utilize experiments or numerical modeling to thoroughly investigate the mechanical behavior of columns made of hybrid fiber-reinforced geopolymer concrete (HFRGC) and reinforced with basalt fiber reinforced polymer (BFRP) bars. This research aims to investigate and assess the mechanical performance of steel-reinforced HFRGC columns (SRHC) and BFRP-reinforced HFRGC columns (GRHC) in concentric and eccentric loading conditions through experimental testing and finite element analysis (FEA). HFRGC specimens were prepared using steel and polypropylene fibers. Twelve circular columns, six GRHC, and six SRHC specimens, were constructed with a diameter of 300 mm and a height of 1200 mm. The average axial strength (AS) of GRHC columns was found to be 92.13% of that of SRHC columns, according to the study. Under eccentric stress circumstances, both kinds of specimens showed comparable losses in AS; for example, GRHC specimens with 38 mm spiral spacing showed reductions of 39.01% and 43.12%. Good performance was shown by the suggested analytical relationships that were drawn from the experimental data. The AS of GRHC columns may be predicted using the newly established analytical and FEA models, which are well supported by this comparative analysis that takes into account the wrapping impact of lateral BFRP spirals and the axial participation of primary BFRP bars.