(1 同济大学土木工程学院, 上海 200092; 2 广西大学土木建筑工程学院, 南宁 530004)

摘要: 石粉含量对机制砂混凝土的性能有较大的影响. 对不同石粉含量的机制砂混凝土梁开展受弯试验,对比研究了不同石粉含量机制砂混凝土梁和天然砂混凝土梁受弯破坏形式、极限荷载、钢筋和混凝土应变以及梁跨中挠度等. 结果表明,机制砂混凝土的抗压强度和弹性模量随石粉含量的增加先增大再减小,当石粉含量范围在 5% ~ 15%时,机制砂混凝土的抗压强度和弹性模量优于天然砂混凝土. 与天然砂混凝土梁相比,石粉含量为 5%和 10%的机制砂混凝土梁受弯极限承载力分别提高了 50%和 52%,开裂荷载分别增加了 70%和 75%,当石粉含量为 10%时,试验梁极限荷载最大. 合适的石粉含量对机制砂混凝土梁受弯性能的提升有较好的促进作用,建议石粉含量取为 5%~10%.

关键词: 机制砂; 石粉; 混凝土梁; 受弯性能; 破坏模式

中图分类号:TU528 文献标志码:A 文章编号:1002-848X(2023)12-0074-06

DOI:10. 19701 / j. jzjg. 20211543

Experimental study and analysis on flexural behavior of concrete beams with manufactured sand

BAI Meiyan1,2, WU Yuching1, XIAO Jianzhuang1, XIE Kaizhong2

(1 College of Civil Engineering, Tongji University, Shanghai 200092, China; 2 College of Civil Engineeringand Architecture, Guangxi University, Nanning 530004, China)

Abstract: The stone powder content has a great influence on the performance of manufactured sand concrete. The bendingtests of manufactured sand concrete beams with different stone powder content were carried out, the bending failure forms ofmanufactured sand concrete beams with different stone powder content and natural sand concrete beams, the ultimate load,strain and deflection of reinforcement and concrete, and mid span deflection were studied. The results show that thecompressive strength and elastic modulus of manufactured sand concrete first increase and then decrease with the increase ofstone powder content. When the stone powder content ranges from 5% to 15%, the compressive strength and elasticmodulus of manufactured sand concrete are better than natural sand concrete. Compared with natural sand concrete beams,the ultimate bearing capacity of manufactured sand concrete beams with stone powder content of 5% and 10% is increasedby 50% and 52% respectively, and the cracking load is increased by 70% and 75% respectively. When the stone powdercontent is 10%, the ultimate load of the test beam is the largest. The appropriate content of stone powder can promote theimprovement of flexural performance of manufactured sand concrete beams, and it is suggested that the content of stonepowder should be 5% to 10%.

Keywords:manufactured sand; stone powder; concrete beam; flexural performance; failure mode

∗国家自然科学基金项目(51868007,51368005).

第一作者:柏美岩,硕士,主要从事新型混凝土材料及废弃物资源化,Email: baimeiyan@ tongji. edu.

[引用本文] 柏美岩,吴宇清,肖建庄,等. 机制砂混凝土梁受弯性能试验研究与分析[ J]. 建筑结构,2023,53(12):74-79. BAI Meiyan,WU Yuching,XIAO Jianzhuang,et al. Experimental study and analysis on flexural behavior ofconcrete beams with manufactured sand[J]. Building Structure,2023,53(12):74-79.