Table 4 Effect of CaO as a sole activator on the properties of different matrices
References | Precursor | Sole activator | Ratio | Type | Curing condition | Main results |
|---|---|---|---|---|---|---|
Yum et al., (2019) | Slag | CaO | 4 | Paste | 23 °C with 99% RH | - The flowability, initial setting time and final setting time was 16.5 mm, 540 min and 1140 min - The 3, 7 and 28 days compressive strength was 7.15, 16.25 and 27.5 MPa - The 3 and 28 days total porosity was 39.45% and 38.51% |
Yum et al., (2020) | Slag | CaO | 4 | Paste | 23 °C with 99% RH | - The 3, 7 and 28 days compressive strength was 7.15, 16.25 and 27.5 MPa - The 28 days total porosity was 36.8% |
Kolhe et al., (2022) | Slag | Calcium carbide (source for CaO) | 4–16 | Paste | 23 ± 2 °C with 65% RH | - Increased CaO concentration decreased flowability, shortened setting time and increased compressive strength and thermal conductivity |
Park et al., (2016a) | Slag | CaO | 5 | Paste | 23 °C with 99% RH | - The 7 and 28 days compressive strength was ~ 20.5 and ~ 39 MPa |
Dahal et al., (2023) | Slag | CaO | 5 | UHPC | 23 °C with 99% RH for 24 h, then, at 90 °C for 48 h | - The flow of the mixture was 265% - The compressive strength and tensile strength was 110 and 9 MPa |
Oinam et al., (2023) | Slag | CaO | 5 | UHPC | 23 °C with 99% RH for 24 h, then, at 90 °C for 48 h | - The compressive strength and tensile strength was 180 and 12.75 MPa |
Burciaga-DÃaz et al., (2023) | Slag | CaO | 6 | Paste | 20 ± 2 °C with 80% RH for 90 days | - The 1, 3, 7, 14, 28 and 90 days compressive strength was ~ 0, ~ 3.75, ~ 8.5, ~ 17.5, 20 MPa |
|  | Slag | CaO | 6 | Paste | 60 °C for 24 h, then at 20 °C up to 90 days | - The 1, 3, 7, 14, 28 and 90 days compressive strength ~ 5, ~ 5, ~ 5.5, ~ 7, ~ 7.5 and ~ 12.5 MPa |
Kim et al., (2013) | Slag | CaO | 6.25 | Paste | 25 °C with 99% RH | - The 1, 3, 7, 14, 28 and 56 days compressive strength was 3.3, 18, 31, 34, 42 and 53 MPa |
Wang et al., (2018) | Slag | CaO | 7.5 | Paste | 20 ± 1 °C with ≥ 90% RH | - The 7 and 28 days compressive strength was ~ 15 and 22 MPa |
Tian et al., (2021) | Slag | CaO | 8 | Paste | Room | - The initial setting time was 360 and 390Â min, whilst the final setting time was 480 and 520Â min - The 3Â days compressive strength was 4.49 and 0.45Â MPa, whilst the 28Â days compressive strength was 9.3 and 5.64Â MPa |
Park et al., (2016b) | Slag | CaO | 2, 5 and 10 | Paste | 23 °C with 99.9% RH | - The compressive strength increased with increasing CaO concentration - The 3, 7 and 28 days compressive strength for the specimens activated with 10% CaO was ~ 11, ~ 16.5 and ~ 27 MP |
Jeong et al., (2016) | Slag | CaO | 10 | Paste | 23 °C with > 95% RH | - The 28 days compressive strength was in the range of 25–52 MPa according to the slag type |
Gu et al., (2014) | Slag | CaO | 10 | Paste | Water 20 ± 2 °C | - The 7, 28 and 90 days was 25, ~ 32.5 and ~ 39 MPa |
|  | Slag | CaO | 10 | Paste | 20 ± 2 °C with 99 ± 1% RH | - The 7, 28 and 90 days was ~ 25, ~ 31 and ~ 34 MPa |
Djayaprabha and Nguyen, (2023) | Slag | CaO | 15 | Paste | Ambient | - The flow and fresh density was 115% and 2134.88 kg/m3 - The 3–56 days compressive strength and 3–56 flexural strength was ~ 9- ~ 27 MPa and ~ 2.1- ~ 5.4 MPa |
FA | CaO | 15 | Paste | 60 °C with 95% RH for 24 h | - The 1, 3, 7 and 28 days compressive strength was 1, 7.4, 8.3 and 12 MPa | |
Zhao et al., (2020a) | 70% FA/13% cement | CaO | 17 | Paste | Autoclaved at 140 °C. 180 °C and 210 °C for 3–12 h | - Higher compressive strength with higher autoclave temperature and longer autoclave period |