Mechanical Behavior of Fly-Ash Geopolymer Under Stray-Current and Soft-Water Coupling
Stray-current and soft-water leaching can induce severe corrosion in reinforced concrete structures and buried metal pipelines within subway environments. The effects of water-to-binder ratio (W/C), modulus of sodium silicate (Ms), and alkali content (AC) on the mechanical properties of fly-ash-base...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-07-01
|
| Series: | Buildings |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-5309/15/14/2514 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849246507998380032 |
|---|---|
| author | Ran Tang Fang Liu Baoming Wang Xiaojun Wang Cheng Hua Xiaosa Yuan |
| author_facet | Ran Tang Fang Liu Baoming Wang Xiaojun Wang Cheng Hua Xiaosa Yuan |
| author_sort | Ran Tang |
| collection | DOAJ |
| description | Stray-current and soft-water leaching can induce severe corrosion in reinforced concrete structures and buried metal pipelines within subway environments. The effects of water-to-binder ratio (W/C), modulus of sodium silicate (Ms), and alkali content (AC) on the mechanical properties of fly-ash-based geopolymer (FAG) at various curing ages were investigated. The influence of curing temperature and high-temperature curing duration on the development of mechanical performance were examined, and the optimal curing regime was determined. Furthermore, based on the mix design of FAG resistant to coupled erosion from stray-current and soft-water, the effects of stray-current intensity and erosion duration on the coupled erosion behavior were analyzed. The results indicated that FAG exhibited slow strength development under ambient conditions. However, thermal curing at 80 °C for 24 h markedly improved early-age strength. The compressive strength of FAG exhibited an increase followed by a decrease with increasing W/B, Ms, and AC, with optimal ranges identified as 0.28–0.34, 1.0–1.6, and 4–7%, respectively. Soft-water alone caused limited leaching, while the presence of stray-current significantly accelerated degradation, with corrosion rates increasing by 4.1 and 7.2 times under 20 V and 40 V, respectively. The coupled corrosion effect was found to weaken over time and with increasing current intensity. Under coupled leaching conditions, compressive strength loss of FAG was primarily influenced by AC, with lesser contributions from W/B and Ms. The optimal mix proportion for corrosion resistance was determined to be W/B of 0.30, Ms of 1.2, and AC of 6%, under which the compressive strength after corrosion achieved the highest value, thereby significantly improving the durability of FAG in harsh environments such as stray-current zones in subways. |
| format | Article |
| id | doaj-art-b76f0c834e544dd68467ba8cc07fb38a |
| institution | Kabale University |
| issn | 2075-5309 |
| language | English |
| publishDate | 2025-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Buildings |
| spelling | doaj-art-b76f0c834e544dd68467ba8cc07fb38a2025-08-20T03:58:27ZengMDPI AGBuildings2075-53092025-07-011514251410.3390/buildings15142514Mechanical Behavior of Fly-Ash Geopolymer Under Stray-Current and Soft-Water CouplingRan Tang0Fang Liu1Baoming Wang2Xiaojun Wang3Cheng Hua4Xiaosa Yuan5Shaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi’an 710123, ChinaShaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi’an 710123, ChinaSchool of Civil Engineering, Dalian University of Technology, Dalian 116023, ChinaSchool of Civil Engineering, Dalian University of Technology, Dalian 116023, ChinaCollege of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, ChinaShaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi’an 710123, ChinaStray-current and soft-water leaching can induce severe corrosion in reinforced concrete structures and buried metal pipelines within subway environments. The effects of water-to-binder ratio (W/C), modulus of sodium silicate (Ms), and alkali content (AC) on the mechanical properties of fly-ash-based geopolymer (FAG) at various curing ages were investigated. The influence of curing temperature and high-temperature curing duration on the development of mechanical performance were examined, and the optimal curing regime was determined. Furthermore, based on the mix design of FAG resistant to coupled erosion from stray-current and soft-water, the effects of stray-current intensity and erosion duration on the coupled erosion behavior were analyzed. The results indicated that FAG exhibited slow strength development under ambient conditions. However, thermal curing at 80 °C for 24 h markedly improved early-age strength. The compressive strength of FAG exhibited an increase followed by a decrease with increasing W/B, Ms, and AC, with optimal ranges identified as 0.28–0.34, 1.0–1.6, and 4–7%, respectively. Soft-water alone caused limited leaching, while the presence of stray-current significantly accelerated degradation, with corrosion rates increasing by 4.1 and 7.2 times under 20 V and 40 V, respectively. The coupled corrosion effect was found to weaken over time and with increasing current intensity. Under coupled leaching conditions, compressive strength loss of FAG was primarily influenced by AC, with lesser contributions from W/B and Ms. The optimal mix proportion for corrosion resistance was determined to be W/B of 0.30, Ms of 1.2, and AC of 6%, under which the compressive strength after corrosion achieved the highest value, thereby significantly improving the durability of FAG in harsh environments such as stray-current zones in subways.https://www.mdpi.com/2075-5309/15/14/2514stray-currentsoft-water dissolutionfly-ash geopolymermechanical properties |
| spellingShingle | Ran Tang Fang Liu Baoming Wang Xiaojun Wang Cheng Hua Xiaosa Yuan Mechanical Behavior of Fly-Ash Geopolymer Under Stray-Current and Soft-Water Coupling Buildings stray-current soft-water dissolution fly-ash geopolymer mechanical properties |
| title | Mechanical Behavior of Fly-Ash Geopolymer Under Stray-Current and Soft-Water Coupling |
| title_full | Mechanical Behavior of Fly-Ash Geopolymer Under Stray-Current and Soft-Water Coupling |
| title_fullStr | Mechanical Behavior of Fly-Ash Geopolymer Under Stray-Current and Soft-Water Coupling |
| title_full_unstemmed | Mechanical Behavior of Fly-Ash Geopolymer Under Stray-Current and Soft-Water Coupling |
| title_short | Mechanical Behavior of Fly-Ash Geopolymer Under Stray-Current and Soft-Water Coupling |
| title_sort | mechanical behavior of fly ash geopolymer under stray current and soft water coupling |
| topic | stray-current soft-water dissolution fly-ash geopolymer mechanical properties |
| url | https://www.mdpi.com/2075-5309/15/14/2514 |
| work_keys_str_mv | AT rantang mechanicalbehaviorofflyashgeopolymerunderstraycurrentandsoftwatercoupling AT fangliu mechanicalbehaviorofflyashgeopolymerunderstraycurrentandsoftwatercoupling AT baomingwang mechanicalbehaviorofflyashgeopolymerunderstraycurrentandsoftwatercoupling AT xiaojunwang mechanicalbehaviorofflyashgeopolymerunderstraycurrentandsoftwatercoupling AT chenghua mechanicalbehaviorofflyashgeopolymerunderstraycurrentandsoftwatercoupling AT xiaosayuan mechanicalbehaviorofflyashgeopolymerunderstraycurrentandsoftwatercoupling |