(黄淮学院建筑工程学院, 驻马店 463000)

摘要: 为了研究再生骨料对自密实混凝土力学和长期性能的影响规律,以再生骨料的掺量与级配为变量,制备了4 种不同配合比的自密实混凝土拌合物,对其抗压强度、劈裂抗拉强度和抗折强度进行了测试,并对其孔径分布和长期徐变行为机理进行了分析. 结果表明:采用再生骨料制备自密实混凝土是可行的,适当掺入再生骨料不会显著影响自密实混凝土的和易性和间隙通过性. 在适当的再生骨料取代率下,自密实混凝土的力学性能可以等于甚至高于对照组;自密实混凝土的微观结构受再生骨料的掺量和级配的影响显著,这造成了混凝土中微孔、介孔和大孔数量的显著差异,进而影响了其短期的新拌性能和长期的收缩应力及徐变行为.

关键词: 自密实混凝土; 再生骨料; 孔隙率; 长期性能

中图分类号:TU528. 01 文献标志码:A 文章编号:1002-848X(2023)12-0087-04

DOI:10. 19701 / j. jzjg. 20210151

Research on mechanical and long-term performance of recycled aggregate self-compacting concrete

YI Qinggang, JU Huahua, ZHANG Qizhi

(Institute of Architecture Engineering, Huanghuai University, Zhumadian 463000, China)

Abstract: In order to reveal the influence of recycled aggregates on the mechanical and long-term performance of selfcompacting concrete, four self-compacting concrete mixtures with different mix ratios were prepared with the content andgradation of recycled aggregates as variables, and their compressive strength, split tensile strength and flexural strengthwere tested, and its pore size distribution and long-term creep behavior mechanism were analyzed. The results show that itis feasible to prepare self-compacting concrete by using recycled aggregate, and appropriate addition of recycled aggregatewill not significantly affect the workability and clearance permeability of self-compacting concrete. The mechanicalproperties of self-compacting concrete can be equal to or even higher than those of the control group. The microstructure ofself-compacting concrete is significantly affected by the content and gradation of recycled aggregates. The significantdifference in the number of micropores, mesopores and macropores in concrete has been found to affect its short-term freshmixing performance and long-term shrinkage stress and creep behavior.

Keywords:self-compacting concrete; recycled aggregate; porosity; long-term performance

∗国家自然科学基金项目(51778105),绿色高性能混凝土材料及其应用研究(ZGYGC1026).

第一作者:伊庆刚,硕士,工程师,主要从事混凝土动态力学特性及损伤机理研究,Email:zdjs_zqz@ 163. com.

[引用本文] 伊庆刚,琚花花,张启志. 再生骨料自密实混凝土力学与长期性能研究[ J]. 建筑结构,2023,53(12):87-90,86. YI Qinggang,JU Huahua,ZHANG Qizhi. Research on mechanical and long-term performance of recycledaggregate self-compacting concrete[J]. Building Structure,2023,53(12):87-90,86.