Regulatory Mechanism of SAC Content in Chloride Binding Characteristics of Ternary Repair Materials
Abstract
1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Sample Preparation
2.3. Test Methods
2.3.1. Determination of Chloride Ion Content in Cementitious Materials
2.3.2. Rapid Chloride Permeability Test
2.3.3. Microstructure
3. Results and Discussion
3.1. Effect of Hydration Age on Chloride Binding Capacity of the OPC-GGBS-SAC
3.2. Effect of Exposure Time on Chloride Binding Capacity of the OPC-GGBS-SAC
3.3. Effect of SAC Content on Chloride Penetration Resistance of OPC-GGBS-SAC Repair Mortar
3.4. Chloride Binding Mechanism of OPC-GGBS-SAC Composite System
3.4.1. XRD Analysis
3.4.2. TG Analysis
3.4.3. SEM-EDS Analysis
4. Conclusions
- (1)
- SAC effectively reduced the chloride penetration resistance of the OPC-GGBS-SAC ternary system. At an SAC proportion of 10%, the electric flux reached its minimum value, which decreased by 28.9% compared to the blank group.
- (2)
- A low percentage of SAC accelerated the hydration process of the ternary system, enhanced the degree of hydration, and generated more hydration products, including the AFm phase, which binds chlorides. When the SAC content was 10%, the chloride binding ratio of the composite system reached its maximum, representing an increase of 3.92% compared with the control group. When the SAC content further increased beyond this level, the extent of hydration of the ternary materials was adversely affected, causing a decline in chloride binding capacity.
- (3)
- When the SAC content exceeded 10%, the primary reason for the reduction in chloride ion binding ability was that the SAC replaced the OPC and GGBS in the system, which reduced the amount of AFm formed. Therefore, when using SAC to modify composite systems, it is particularly important to keep the dosage within a reasonable range to enhance the capability to bind chloride ions of the ternary materials.
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
- Fan, L.; Liang, Z.; Shen, W.; Sun, B.; Zhang, R. Investigation of the impact of protective layer thickness and chloride ion penetration direction on macro-cell corrosion of reinforcement in mortar columns under marine environment. Constr. Build. Mater. 2025, 489, 142197. [Google Scholar] [CrossRef]
- Xu, L.; Li, W.; Long, J.; Liu, S.; Xu, M.; Guo, J.; Wu, K. Insights into the role of slag fineness on the hydration of slag-sulfoaluminate cement. Constr. Build. Mater. 2024, 447, 138106. [Google Scholar] [CrossRef]
- He, H.; Qiao, H.; Sun, T.; Yang, H.; He, C. Research progress in mechanisms, influence factors and improvement routes of chloride binding for cement composites. J. Build. Eng. 2024, 86, 108978. [Google Scholar] [CrossRef]
- Zhang, Q.; Xu, G.; Li, X.; Chen, J.; Liu, Z. Effect of chloride ions on strength and hydration mechanisms of alkali-activated-GGBS solidified soft clay in marine environment. Constr. Build. Mater. 2025, 493, 143297. [Google Scholar]
- Xue, J.; Li, S.; Zhang, Z.; Liu, S.; Li, G.; Guan, X. Hydration, mechanical properties, and corrosion resistance of ferroaluminate cement in the presence of FA and GGBS. J. Build. Eng. 2025, 102, 111974. [Google Scholar] [CrossRef]
- Luo, R.; Cai, Y.; Wang, C.; Huang, X. Study of chloride binding and diffusion in GGBS concrete. Cem. Concr. Res. 2003, 33, 1–7. [Google Scholar] [CrossRef]
- Li, X.; Xu, F.; Chen, B.; Li, B.; Chen, Z.; Zhu, J.; Chao, P.; Lin, J. Investigation on the chloride ion erosion mechanism of cement mortar in coastal areas: From experiments to molecular dynamics simulation. Constr. Build. Mater. 2022, 350, 128810. [Google Scholar] [CrossRef]
- Liu, R.; Li, X.; Zhang, Z.; Zhang, X. Effect of ground granulated blast-furnace slag (GGBS) and sulphoaluminate cement (SAC) on the strength and microstructure of ordinary Portland cement paste at elevated temperatures. Powder Technol. 2024, 448, 120226. [Google Scholar] [CrossRef]
- Zhang, P.; Qi, D.; Hao, L.; Wang, Z.; Liu, H.; Zhang, D.; Xie, Y.; Zhao, E. Effect of w/b ratio and supplemental cementitious material on the chloride penetration and corrosion resistance of ferroaluminate cement concrete. Constr. Build. Mater. 2024, 431, 136481. [Google Scholar] [CrossRef]
- Gao, Y.; Xu, W.; Huang, G.; Li, W.; Cheng, Z. Research on early-age properties and hydration mechanisms of slaked lime-sodium carbonate activated GGBS-sulphoaluminate cement grouting materials. Constr. Build. Mater. 2026, 519, 145888. [Google Scholar]
- Li, H.; Farzadnia, N.; Zhao, Y.; Hu, X.; Shi, C. Effects of SCMs on chloride binding capacity of ultra-low water-to-binder ratio cement paste with internally introduced chloride. Constr. Build. Mater. 2024, 413, 134725. [Google Scholar]
- Patrick, A.; Gabriel, S.; Fabrice, D.; Vincent, T.; Hugo, L.; Virginie, B.; Martion, C. Transfer properties and chloride-induced corrosion resistance of GGBS and metakaolin alkali-activated materials. Cem. Concr. Compos. 2023, 142, 105182. [Google Scholar]
- Wen, C.; Li, J.; Meng, Q.; Yang, S.; Chen, Z.; Wang, X.; Li, Y.; Wang, X.; Sun, X.; Mu, L.; et al. Study of macro-/micro-properties and in-situ mineralization mechanism of CO2 foam concrete based on solid waste-derived SAC-gypsum composite. Constr. Build. Mater. 2025, 486, 141911. [Google Scholar]
- Yan, Y.; Geng, G. Quantification of GGBS hydration using deep learning—A comparison with SEM-EDS mapping, PONKCS XRD and isothermal calorimetry methods. Cem. Concr. Res. 2025, 197, 107960. [Google Scholar]
- Yu, L.; Jiang, L.; Chu, H.; Guo, M.; Zhu, Z.; Dong, H. Effect of electrochemical chloride removal and ground granulated blast furnace slag on the chloride binding of cement paste subjected to NaCl and Na2SO4 attack. Constr. Build. Mater. 2019, 220, 538–546. [Google Scholar]
- Zhang, T.; Tian, W.; Guo, Y.; Bogush, A.; Khayrulina, E.; Wei, J.; Yu, Q. The volumetric stability, chloride binding capacity and stability of the Portland cement-GBFS pastes: An approach from the viewpoint of hydration products. Constr. Build. Mater. 2019, 205, 357–367. [Google Scholar] [CrossRef]
- Ye, H.; Cartwright, C.; Rajabipour, F.; Radlińska, A. Understanding the drying shrinkage performance of alkali-activated slag mortars. Cem. Concr. Compos. 2017, 76, 13–24. [Google Scholar] [CrossRef]
- Li, G.; Zhang, A.; Song, Z.; Liu, S.; Zhang, J. Ground granulated blast furnace slag effect on the durability of ternary cementitious system exposed to combined attack of chloride and sulfate. Constr. Build. Mater. 2018, 158, 640–648. [Google Scholar] [CrossRef]
- Cheng, Z.; Ji, L.; Wang, Z.; Gu, L.; Tang, W. Exploration of the chloride binding behavior of anhydrous calcium sulfoaluminate under dual chloride ingress modes. Materials 2025, 18, 4949. [Google Scholar] [CrossRef] [PubMed]
- Wang, Y.; Chen, J.; Yao, T. Comparative study on alkali resistances of ordinary Portland cement (OPC) and sulfoaluminate cement (SAC). Constr. Build. Mater. 2025, 495, 143618. [Google Scholar] [CrossRef]
- Mohammad, A.; Elke, G.; Kim, V.; Nele, D. New findings on the contribution of Mg-Al-NO3 layered double hydroxides to the hydration and chloride binding capacity of cement pastes. Cem. Concr. Res. 2023, 163, 107037. [Google Scholar]
- He, X.; Yang, J.; Niu, M.; Asad, H.; Li, G. Contribution of layered double hydroxides to hydration and chloride binding capacity of OPC-SAC-GGBS repair materials. Constr. Build. Mater. 2024, 416, 135203. [Google Scholar]
- Xin, X.; Duan, G.; Huang, Y.; Li, J.; Li, C.; Hou, P. Study on the hydration of slag-belite calcium sulfoaluminate-Portland cement composite cementitious system. Constr. Build. Mater. 2024, 433, 136713. [Google Scholar]
- Sun, H.; Huo, Y.; Xu, Z.; Chen, Z.; Yang, Y. Mechanical properties and its prediction of sulphoaluminate cement-engineered cementitious composites (SAC-ECC) as rapid repair materials applied in winter construction. Cem. Concr. Compos. 2025, 160, 106016. [Google Scholar]
- Zhou, Q.; Cao, R.; Ma, X. Effects of multi-walled carbon nanotubes on mechanical properties and microstructure of ordinary Portland cement-sulfoaluminate cement repair mortar. Materials 2025, 18, 3748. [Google Scholar] [PubMed]
- Wang, Y.; Li, Y.; Yang, Z.; Chang, T.; Sun, L. Effect of OPC-SAC composite cementitious system on the properties of ultra-high performance concrete. Mater. Rep. 2025, 39, 94–100. (In Chinese) [Google Scholar]
- He, X.; Zhang, W.; Liu, Y.; Zhang, Y.; Yu, Y.; Niu, M.; Li, G. Study on the Interfacial Bonding Behavior of OPC-GGBS-SAC Composite Repair Materials. Buildings 2025, 15, 4124. [Google Scholar]
- GB/T 18046-2017; Ground Granulated Blast Furnace Slag Used for Cement, Mortar and Concrete. China Standards Press: Beijing, China, 2017.
- GB 175-2023; Common Portland Cement. China Standards Press: Beijing, China, 2023.
- GB/T 20472-2026; Sulphoaluminate Cement. China Standards Press: Beijing, China, 2026.
- GB/T 50448-2015; Code for Application Technique of Cementitious Grout. China Architecture and Building Press: Beijing, China, 2025.
- Hu, Y.; Li, H.; Wang, Q.; Zhang, J.; Song, Q. Characterization of LDHs prepared with different activity MgO and resisting Cl− attack of concrete in salt lake brine. Constr. Build. Mater. 2019, 229, 116921. [Google Scholar] [CrossRef]
- GB/T 176-2025; Methods for Chemical Analysis of Cement. China Standards Press: Beijing, China, 2025.
- Tang, L.; Nilsson, L. Chloride binding capacity and binding isotherms of OPC pastes and mortars. Cem. Concr. Res. 1993, 23, 247–253. [Google Scholar] [CrossRef]
- GB/T 50082-2024; Standard for Test Methods of Long-Term Performance and Durability of Concrete. China Architecture and Building Press: Beijing, China, 2024.
- Aydoğan, O.G.; Dilber, A.A.; Özyurt, N. Friedel’s salt stability and sulfate durability of seawater mixed cement-based material. J. Build. Eng. 2025, 110, 113124. [Google Scholar]
- Zhao, Y.; Hu, X.; Yuan, Q.; Shi, C. The change of phase assemblage and desorption of bound chloride for seawater cement paste under sulfate attack. Cem. Concr. Compos. 2023, 139, 105033. [Google Scholar] [CrossRef]
- Das, C.S.; Ahmad, M.R.; Dai, J. Influences of temperatures on the physical and chemical chloride binding of calcium silicate hydrate and Friedel salt at different chloride concentrations. Constr. Build. Mater. 2025, 476, 141303. [Google Scholar] [CrossRef]
- Zhang, Y.; Chang, J.; Ji, J. AH3 phase in the hydration product system of AFt-AFm-AH3 in calcium sulfoaluminate cements: A microstructural study. Constr. Build. Mater. 2018, 167, 587–596. [Google Scholar]
- Lv, Z.; Tan, H.; Liu, X.; Chen, P.; Wang, Y.; Liang, W.; Hong, J. Chloride binding of AFm in the presence of Na, Ca2+ and Ba2+. Constr. Build. Mater. 2023, 364, 129804. [Google Scholar] [CrossRef]
- Chen, J.; Zeng, L.; Wang, W.; Qian, M.; Zhao, S.; Zhu, B. Influence of main components of accelerators on mechanical property and hydration of Portland cement in a dry-hot geothermal environment. Constr. Build. Mater. 2023, 394, 132290. [Google Scholar] [CrossRef]
- Li, B.; Hu, J.; Chen, L.; Zhang, J.; Gu, J. Strength and its microstructure evolution of GGBS-FA geopolymer mortar under seawater. Case Stud. Constr. Mater. 2025, 22, e04662. [Google Scholar] [CrossRef]
- Cao, R.; Zhao, H.; Liu, P.; Xu, L.; Jia, Z.; Zhang, S. Carbonation behavior of GGBS with different reactivity and its regulatory effects on early hydration performance in alkali-activated system. Constr. Build. Mater. 2026, 512, 145393. [Google Scholar] [CrossRef]
- Huang, X.; Hu, S.; Wang, F.; Lu, Y.; Rao, M.; Mu, Y.; Wang, C. The effect of supplementary cementitious materials on the permeability of chloride in steam cured high-ferrite Portland cement concrete. Constr. Build. Mater. 2019, 197, 99–106. [Google Scholar] [CrossRef]
- Jian, G.; Chong, G.; Yu, W.; Chen, W.; Zhu, Y. Chloride binding in cement paste with calcined Mg-Al-CO3 LDH (CLDH) under different conditions. Constr. Build. Mater. 2020, 27, 121678. [Google Scholar]
- Cai, Y.; Tao, Y.; Xuan, D.; Zhu, X.; Chi, S. Effects of seawater on the formation and mechanical properties of Friedel’s salt associated with tricalcium aluminate. Cem. Concr. Res. 2023, 174, 107340. [Google Scholar]










| CaO | Al2O3 | SiO2 | Fe2O3 | MgO | SO3 | K2O | Na2O | LOI | |
|---|---|---|---|---|---|---|---|---|---|
| OPC | 63.23 | 5.29 | 20.38 | 2.98 | 2.11 | 2.46 | 0.37 | 0.15 | 3.03 |
| SAC | 42.25 | 36.46 | 6.86 | 2.20 | 1.33 | 8.82 | 0.18 | 0.22 | 1.25 |
| GGBS | 40.81 | 18.46 | 31.55 | 2.42 | 4.13 | 2.05 | 0.24 | 0.13 | 0.21 |
| Specific Surface Area (m2/kg) | Setting Time (min) | Compressive Strength (MPa) | |||||
|---|---|---|---|---|---|---|---|
| Initial | Final | 1 d | 3 d | 7 d | 28 d | ||
| OPC | 362 | 168 | 213 | / | 36.2 | 40.3 | 55.7 |
| SAC | 350 | 30 | 65 | 30.5 | / | 45.0 | 47.9 |
| Density (kg/m3) | Specific Surface Area (m2/kg) | Activity Index (%) | Flowability Ratio (%) | |
|---|---|---|---|---|
| 7 d | 28 d | |||
| 2875 | 462 | 79 | 98 | 102 |
| Mix ID | OPC (g) | GGBS (g) | SAC (g) | S (g) | PCE (g) | W (g) | Initial Fluidity (mm) |
|---|---|---|---|---|---|---|---|
| S0 | 700 | 300 | 0 | 1000 | 4.00 | 230 | 330 |
| S5 | 665 | 285 | 50 | 1000 | 4.00 | 230 | 330 |
| S10 | 630 | 270 | 100 | 1000 | 4.00 | 230 | 325 |
| S15 | 595 | 255 | 150 | 1000 | 4.00 | 230 | 325 |
| S20 | 560 | 240 | 200 | 1000 | 4.00 | 230 | 330 |
| Mix ID | OPC (g) | GGBS (g) | SAC (g) | PCE (g) | W (g) |
|---|---|---|---|---|---|
| S0 | 700 | 300 | 0 | 2.00 | 230 |
| S5 | 665 | 285 | 50 | 2.00 | 230 |
| S10 | 630 | 270 | 100 | 2.00 | 230 |
| S15 | 595 | 255 | 150 | 2.00 | 230 |
| S20 | 560 | 240 | 200 | 2.00 | 230 |
| Immersion Time (d) | Dosage of SAC (%) | Cf (%) | Cb (%) | Ct (%) | Cl− Binding Rate (%) |
|---|---|---|---|---|---|
| 3 | 0 | 0.6721 | 0.2021 | 0.8741 | 23.1121 |
| 3 | 5 | 0.7191 | 0.2561 | 0.9751 | 26.2564 |
| 3 | 10 | 0.7553 | 0.2797 | 1.0351 | 27.0285 |
| 3 | 15 | 0.8404 | 0.2386 | 1.0791 | 22.1158 |
| 3 | 20 | 0.9001 | 0.2211 | 1.1211 | 19.7145 |
| 7 | 0 | 0.9026 | 0.2316 | 1.1342 | 20.4188 |
| 7 | 5 | 0.9341 | 0.2799 | 1.2141 | 23.0597 |
| 7 | 10 | 1.0079 | 0.2914 | 1.2993 | 22.4259 |
| 7 | 15 | 1.0571 | 0.2501 | 1.3071 | 19.1278 |
| 7 | 20 | 1.1228 | 0.2262 | 1.3491 | 16.7692 |
| 14 | 0 | 0.9941 | 0.3101 | 1.3041 | 23.773 |
| 14 | 5 | 1.0071 | 0.3511 | 1.3581 | 25.8468 |
| 14 | 10 | 1.0861 | 0.4011 | 1.4871 | 26.9671 |
| 14 | 15 | 1.1751 | 0.3211 | 1.4961 | 21.4572 |
| 14 | 20 | 1.2075 | 0.2975 | 1.5051 | 19.7664 |
| 28 | 0 | 1.0861 | 0.3131 | 1.3991 | 22.3731 |
| 28 | 5 | 1.1491 | 0.3531 | 1.5021 | 23.5021 |
| 28 | 10 | 1.1791 | 0.4021 | 1.5811 | 25.4269 |
| 28 | 15 | 1.2691 | 0.3231 | 1.5921 | 20.2889 |
| 28 | 20 | 1.2981 | 0.3031 | 1.6011 | 18.9257 |
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He, X.; Niu, M.; Zhou, H.; He, J.; Xie, H.; Hu, C.; Qian, L.; Li, F. Regulatory Mechanism of SAC Content in Chloride Binding Characteristics of Ternary Repair Materials. Materials 2026, 19, 2862. https://doi.org/10.3390/ma19132862
He X, Niu M, Zhou H, He J, Xie H, Hu C, Qian L, Li F. Regulatory Mechanism of SAC Content in Chloride Binding Characteristics of Ternary Repair Materials. Materials. 2026; 19(13):2862. https://doi.org/10.3390/ma19132862
Chicago/Turabian StyleHe, Xiang, Mengdie Niu, Heng Zhou, Jingjing He, Honglin Xie, Cunbao Hu, Li Qian, and Fangping Li. 2026. "Regulatory Mechanism of SAC Content in Chloride Binding Characteristics of Ternary Repair Materials" Materials 19, no. 13: 2862. https://doi.org/10.3390/ma19132862
APA StyleHe, X., Niu, M., Zhou, H., He, J., Xie, H., Hu, C., Qian, L., & Li, F. (2026). Regulatory Mechanism of SAC Content in Chloride Binding Characteristics of Ternary Repair Materials. Materials, 19(13), 2862. https://doi.org/10.3390/ma19132862
