预应力锚杆自由段水泥灌浆材料性能及配合比优化

Performance of the Cement Grouting Material and Optimization of the Mix Proportion for the Free Section of the Prestressed Anchor Bar.

作者信息

Wu Chaoguang, Chen Zhiya, Zhang Xuemin, Li Zikun, Wang Lichuan, Ouyang Bin, Liu Jin

机构信息

School of Civil Engineering, Central South University, Changsha 410075, China.

School of Transportation, Central South University, Changsha 410075, China.

出版信息

Materials (Basel). 2023 Oct 23;16(20):6819. doi: 10.3390/ma16206819.

DOI:10.3390/ma16206819

PMID:37895799

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10608292/

Abstract

Increasing the water-cement ratio and water-reducer dosage of cement slurry enhances its fluidity. However, a high water-cement ratio diminishes the beneficial effects of water reducers on fluidity. The stone content of the slurry decreases as the water-reducer dosage increases. Additionally, the water-cement ratio significantly affects stone content. However, when the water-cement ratio exceeds a threshold value, stone content decreases. Furthermore, the threshold value of the water-cement ratio decreases with increasing water-reducer dosage. Without the addition of the water reducer, as the water-cement ratio increases the overall integrity of the grout stone decreases. The addition of the water reducer alters the surface pore distribution, wherein "uniform small pores" change to "localized large pores." Based on the multi-objective optimization of Matlab, the recommended optimal mix composition for a slow-setting cement slurry is a water-cement ratio of 0.25 and water-reducer dosage of 1.5%. With the use of this optimized mix composition, the stone content and compressive strength increase by 7.8% and 145.6%, respectively, compared to those obtained using the recommended mix ratio in the specifications. Additionally, all relevant performance parameters meet the requirements specified by previous standards.

摘要

提高水泥浆的水灰比和减水剂用量可增强其流动性。然而，高水灰比会削弱减水剂对流动性的有益影响。随着减水剂用量增加，浆液的石含量降低。此外，水灰比对石含量有显著影响。然而，当水灰比超过阈值时，石含量会降低。而且，水灰比的阈值会随着减水剂用量的增加而降低。不添加减水剂时，随着水灰比增加，灌浆石的整体完整性会降低。减水剂的添加改变了表面孔隙分布，其中“均匀小孔”变为“局部大孔”。基于Matlab的多目标优化，缓凝水泥浆推荐的最佳配合比为水灰比0.25、减水剂用量1.5%。使用这种优化后的配合比，与规范中推荐配合比相比，石含量和抗压强度分别提高了7.8%和145.6%。此外，所有相关性能参数均满足先前标准规定的要求。