Effect of fly-ash as fine aggregate on the workability and mechanical properties of cemented paste backfill
An experimental study was conducted to investigate the effect of fly-ash(FA) as a fine aggregate on filling performance. The effect of FA content on the gradation distribution and compactness of the dry mixture is tested. Slump, bleeding rate, and unconfined compressive strength (UCS) of cemented wa...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2022-06-01
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| Series: | Case Studies in Construction Materials |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2214509522001711 |
| _version_ | 1818549004320899072 |
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| author | Shenghua Yin Zepeng Yan Xun Chen Leiming Wang |
| author_facet | Shenghua Yin Zepeng Yan Xun Chen Leiming Wang |
| author_sort | Shenghua Yin |
| collection | DOAJ |
| description | An experimental study was conducted to investigate the effect of fly-ash(FA) as a fine aggregate on filling performance. The effect of FA content on the gradation distribution and compactness of the dry mixture is tested. Slump, bleeding rate, and unconfined compressive strength (UCS) of cemented waste rock-FA backfill (CWFB) samples were also tested at different FA content, solids content, and cement-sand ratio conditions. Results show that FA as a fine aggregate can effectively improve the mixture gradation performance. Short-term (3d/7d) strength increases with FA content, while long-term (28d) strength and slump first increase and then decrease, reaching a maximum value of 8.58 MPa and 27.4 cm respectively at 30% FA content. The bleeding rate first decreased and then stabilized (about 5.2%) with FA content. The UCS showed higher sensitivity to high solid content. The slump reduction rate of samples with high FA content decreases with solid content. Larger cement content will weaken the fluidity. When the cement-sand ratio increased from 1:6–1:4, the slump decreased from 27.5 cm to 23.5 cm, and the bleeding rate decreased to 4.05%. However, the mechanical properties are significantly improved with cement content. This study has positive implications for recycling the FA. |
| first_indexed | 2024-12-12T08:27:47Z |
| format | Article |
| id | doaj.art-8be06658f59541799eb5044df0587b3b |
| institution | Directory Open Access Journal |
| issn | 2214-5095 |
| language | English |
| last_indexed | 2024-12-12T08:27:47Z |
| publishDate | 2022-06-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Case Studies in Construction Materials |
| spelling | doaj.art-8be06658f59541799eb5044df0587b3b2022-12-22T00:31:12ZengElsevierCase Studies in Construction Materials2214-50952022-06-0116e01039Effect of fly-ash as fine aggregate on the workability and mechanical properties of cemented paste backfillShenghua Yin0Zepeng Yan1Xun Chen2Leiming Wang3School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China; Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education, University of Science and Technology Beijing, Beijing 100083, ChinaSchool of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China; Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education, University of Science and Technology Beijing, Beijing 100083, China; Corresponding author at: School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China.School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China; Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education, University of Science and Technology Beijing, Beijing 100083, ChinaSchool of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China; Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education, University of Science and Technology Beijing, Beijing 100083, ChinaAn experimental study was conducted to investigate the effect of fly-ash(FA) as a fine aggregate on filling performance. The effect of FA content on the gradation distribution and compactness of the dry mixture is tested. Slump, bleeding rate, and unconfined compressive strength (UCS) of cemented waste rock-FA backfill (CWFB) samples were also tested at different FA content, solids content, and cement-sand ratio conditions. Results show that FA as a fine aggregate can effectively improve the mixture gradation performance. Short-term (3d/7d) strength increases with FA content, while long-term (28d) strength and slump first increase and then decrease, reaching a maximum value of 8.58 MPa and 27.4 cm respectively at 30% FA content. The bleeding rate first decreased and then stabilized (about 5.2%) with FA content. The UCS showed higher sensitivity to high solid content. The slump reduction rate of samples with high FA content decreases with solid content. Larger cement content will weaken the fluidity. When the cement-sand ratio increased from 1:6–1:4, the slump decreased from 27.5 cm to 23.5 cm, and the bleeding rate decreased to 4.05%. However, the mechanical properties are significantly improved with cement content. This study has positive implications for recycling the FA.http://www.sciencedirect.com/science/article/pii/S2214509522001711Fly-ashCemented waste rock-FA backfillParticle distributionFilling performance |
| spellingShingle | Shenghua Yin Zepeng Yan Xun Chen Leiming Wang Effect of fly-ash as fine aggregate on the workability and mechanical properties of cemented paste backfill Case Studies in Construction Materials Fly-ash Cemented waste rock-FA backfill Particle distribution Filling performance |
| title | Effect of fly-ash as fine aggregate on the workability and mechanical properties of cemented paste backfill |
| title_full | Effect of fly-ash as fine aggregate on the workability and mechanical properties of cemented paste backfill |
| title_fullStr | Effect of fly-ash as fine aggregate on the workability and mechanical properties of cemented paste backfill |
| title_full_unstemmed | Effect of fly-ash as fine aggregate on the workability and mechanical properties of cemented paste backfill |
| title_short | Effect of fly-ash as fine aggregate on the workability and mechanical properties of cemented paste backfill |
| title_sort | effect of fly ash as fine aggregate on the workability and mechanical properties of cemented paste backfill |
| topic | Fly-ash Cemented waste rock-FA backfill Particle distribution Filling performance |
| url | http://www.sciencedirect.com/science/article/pii/S2214509522001711 |
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