摘要
研究了不同掺量聚氨酯乳液下,碱-矿渣-粉煤灰基地聚物(AAFS)体积稳定性变化规律,并对其体积稳定性改善机理予以揭示.研究表明:聚氨酯掺量3％ ～7％时,延长了AAFS的初终凝时间,降低了净浆流动度.聚氨酯的加入,减少了AAFS水化生成物的生成量,降低了砂浆的折压强度,28 d抗压强度为38～45 MPa,28d抗折强度为6.5～7.7 MPa,折压比提高14.8％ ～22.3％,韧性改善明显.聚氨酯与AAFS的交互链接,改善了AAFS的体积变化,56 d收缩率为9.7％ ～28.4％,下降明显.同条件下,PU改性AAFS试件的抗开裂性能明显改善.
Abstract
The volumetric stability changes of different dosages of polyurethane emulsion alkali-slag-fly ash base polymers ( AAFS) are investigated and the improving mechanism of their volumetric stability is revealed. The research shows that when the PU dosage is between 3％ and 7％, it prolongs the initial and final setting time of AAFS and reduces the flowability of the slurry. The addition of polyurethane reduces the generation of hydration products in AAFS, resulting in a decrease in the compressive strength of mortar. The 28-day compressive strength ranges from 38 to 45 MPa, and the 28-day flexural strength ranges from 6. 5 to 7. 7 MPa, with an increase in the flexural-to-compressive strength ratio by 14. 8％ to 22. 3％, indicating a significant improvement in toughness. The interaction between polyurethane and AAFS improves the volumetric changes of AAFS, with a shrinkage rate of 9. 7％ to 28. 4％ at 56 days, showing a significant decrease. Under the same conditions, the cracking resistance of AAFS modified by PU is significantly improved.
基金项目
"十四五"国家重点研发计划项目(2022YFV30803404-02)
维普
万方数据