| In recent years, precipitated calcium carbonate (PCC) and Upcycled Concrete Aggregate
(UCA) have demonstrated potential as sustainable materials for use in the construction industry.
Research on green concrete incorporating PCC and UCA has focused on the axial compressive
strength of plain concrete. However, the effects of steel spiral confinement on such green concrete
have not yet been explored. Therefore, this study examines the stress-strain response of green
concrete with PCC and UCA confined with steel spirals. For this purpose, nine short concrete
columns with 100% UCA and cement replacement with PCC by 15% and 30% were prepared and
confined with steel spirals. Volumetric spiral reinforcement ratios of 1.16, 1.94, and 3.11 were
used. The specimens were subjected to uniaxial compression tests, and load and deformation were
monitored during the test. Spiral reinforcements were found to improve concrete's overall strength
by up to 56.28% and 65.7% for 15% and 30% PCC replacements, respectively. Similarly, peak
strain and ultimate strain with 15% PCC replacement showed increments of up to 58.01% and
184.21%, respectively. For the 30% PCC replacement, these values were 54.24% and 190.38%,
respectively. Moreover, a comparative study of the existing stress-strain models with the test
results indicates that most of the current models are unable to predict the complete stress-strain
behavior of confined green concrete accurately.
Keywords: Precipitated Calcium Carbonate, Upcycled Concrete Aggregate,
Volumetric Spiral Reinforcement Ratio, Uniaxial Compression loading |