Experimental analysis of the chloride diffusion and bonding properties, microstructural performance of concrete in the rainy environment
Frequent exposure to rainfall will obviously induce a change in water saturation of concrete, which will cause the transport of moisture inside concrete, thereby affecting the distributing rules of chloride in concrete. In this study, equipment inside a laboratory was applied to simulate a realistic...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2025-03-01
|
| Series: | Alexandria Engineering Journal |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1110016824016570 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849343696625991680 |
|---|---|
| author | Hesong Jin Lei Cheng Jun Liu Hao Zhou |
| author_facet | Hesong Jin Lei Cheng Jun Liu Hao Zhou |
| author_sort | Hesong Jin |
| collection | DOAJ |
| description | Frequent exposure to rainfall will obviously induce a change in water saturation of concrete, which will cause the transport of moisture inside concrete, thereby affecting the distributing rules of chloride in concrete. In this study, equipment inside a laboratory was applied to simulate a realistic atmospheric rainy environment, and the effect of different rainy conditions (different saturation: 0 %, 50 % and 100 % and different rainfall time: 3 h, 14 h and 48 h) on the ingress of chloride and free or binding chloride concentration of concrete was studied. Besides, the microstructures were studied via Mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results show that the duration time of exposure to rainfall has an important effect on the chloride concentration in the surface area of concrete. The longer it rains, the higher the loss in chloride concentration at the exposed concrete surface is, and the deeper the convection zone is. The changes of the chloride concentration in concrete are strongly dependent on the degree of water saturation. Specifically, at the higher saturation condition, the chloride concentration in concrete layer is quite higher than lower saturation condition, and with a lower saturation, the effect of rainfall condition is more obvious on chloride diffusion in inner area in concrete, and the chloride concentration will decrease faster. In addition, the chloride binding capacity shows a decreasing trend as the saturation decreases. Moreover, the rainfall time has a significant effect on the chloride binding capacity. As the raining time continue to be longer, the chloride binding capacity also decreases. The MIP results show that the longer the rainfall time is, there are the more obvious deteriorating degree of the microstructures and the higher total porosity. Based on the SEM/XRD results, under the same rainy conditions and with lower saturation, more CH or other hydration products are leached out, leading to the looser microstructures in concrete. Besides, the test results of Yangmeikeng Bridge is also similar with the results from the labs in terms of the chloride distribution, hydration products, and total porosity, although the results for the chloride diffusion depth in indoor test is lower than the field test, confirming that the accelerating test in labs can reflect the chloride diffusion behavior. Overall, this study can provide a better insight into a further understanding of the durability design of RC structures in coastal areas. |
| format | Article |
| id | doaj-art-0bbd4a9a3bd24ecaa30df0b26fa2dc9c |
| institution | Kabale University |
| issn | 1110-0168 |
| language | English |
| publishDate | 2025-03-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Alexandria Engineering Journal |
| spelling | doaj-art-0bbd4a9a3bd24ecaa30df0b26fa2dc9c2025-08-20T03:42:53ZengElsevierAlexandria Engineering Journal1110-01682025-03-0111639741410.1016/j.aej.2024.12.059Experimental analysis of the chloride diffusion and bonding properties, microstructural performance of concrete in the rainy environmentHesong Jin0Lei Cheng1Jun Liu2Hao Zhou3Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, PR ChinaGuangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, PR ChinaGuangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, PR China; State Key Laboratory of Intelligent Constrcution and Healthy Operation and Maintenance of Deep Underground Engineering, College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, PR China; Corresponding author at: Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, PR ChinaGuangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, PR ChinaFrequent exposure to rainfall will obviously induce a change in water saturation of concrete, which will cause the transport of moisture inside concrete, thereby affecting the distributing rules of chloride in concrete. In this study, equipment inside a laboratory was applied to simulate a realistic atmospheric rainy environment, and the effect of different rainy conditions (different saturation: 0 %, 50 % and 100 % and different rainfall time: 3 h, 14 h and 48 h) on the ingress of chloride and free or binding chloride concentration of concrete was studied. Besides, the microstructures were studied via Mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results show that the duration time of exposure to rainfall has an important effect on the chloride concentration in the surface area of concrete. The longer it rains, the higher the loss in chloride concentration at the exposed concrete surface is, and the deeper the convection zone is. The changes of the chloride concentration in concrete are strongly dependent on the degree of water saturation. Specifically, at the higher saturation condition, the chloride concentration in concrete layer is quite higher than lower saturation condition, and with a lower saturation, the effect of rainfall condition is more obvious on chloride diffusion in inner area in concrete, and the chloride concentration will decrease faster. In addition, the chloride binding capacity shows a decreasing trend as the saturation decreases. Moreover, the rainfall time has a significant effect on the chloride binding capacity. As the raining time continue to be longer, the chloride binding capacity also decreases. The MIP results show that the longer the rainfall time is, there are the more obvious deteriorating degree of the microstructures and the higher total porosity. Based on the SEM/XRD results, under the same rainy conditions and with lower saturation, more CH or other hydration products are leached out, leading to the looser microstructures in concrete. Besides, the test results of Yangmeikeng Bridge is also similar with the results from the labs in terms of the chloride distribution, hydration products, and total porosity, although the results for the chloride diffusion depth in indoor test is lower than the field test, confirming that the accelerating test in labs can reflect the chloride diffusion behavior. Overall, this study can provide a better insight into a further understanding of the durability design of RC structures in coastal areas.http://www.sciencedirect.com/science/article/pii/S1110016824016570Rainfall timeSaturation levelConcentration distribution of chloride ionsChloride ions binding capacityPoresMicrostructures |
| spellingShingle | Hesong Jin Lei Cheng Jun Liu Hao Zhou Experimental analysis of the chloride diffusion and bonding properties, microstructural performance of concrete in the rainy environment Alexandria Engineering Journal Rainfall time Saturation level Concentration distribution of chloride ions Chloride ions binding capacity Pores Microstructures |
| title | Experimental analysis of the chloride diffusion and bonding properties, microstructural performance of concrete in the rainy environment |
| title_full | Experimental analysis of the chloride diffusion and bonding properties, microstructural performance of concrete in the rainy environment |
| title_fullStr | Experimental analysis of the chloride diffusion and bonding properties, microstructural performance of concrete in the rainy environment |
| title_full_unstemmed | Experimental analysis of the chloride diffusion and bonding properties, microstructural performance of concrete in the rainy environment |
| title_short | Experimental analysis of the chloride diffusion and bonding properties, microstructural performance of concrete in the rainy environment |
| title_sort | experimental analysis of the chloride diffusion and bonding properties microstructural performance of concrete in the rainy environment |
| topic | Rainfall time Saturation level Concentration distribution of chloride ions Chloride ions binding capacity Pores Microstructures |
| url | http://www.sciencedirect.com/science/article/pii/S1110016824016570 |
| work_keys_str_mv | AT hesongjin experimentalanalysisofthechloridediffusionandbondingpropertiesmicrostructuralperformanceofconcreteintherainyenvironment AT leicheng experimentalanalysisofthechloridediffusionandbondingpropertiesmicrostructuralperformanceofconcreteintherainyenvironment AT junliu experimentalanalysisofthechloridediffusionandbondingpropertiesmicrostructuralperformanceofconcreteintherainyenvironment AT haozhou experimentalanalysisofthechloridediffusionandbondingpropertiesmicrostructuralperformanceofconcreteintherainyenvironment |