掺SPA再生混凝土收缩及抗裂性试验研究  

Experimental Study on Shrinkage and Crack Resistance of Recycled Concrete with SPA

作　　者：高飞 GAO Fei(China Railway 18th Bureau Group Municipal Engineering Co.,Ltd.,Tianjin 300222,China)

机构地区：[1]中铁十八局集团市政工程有限公司,天津300222

出　　处：《广东水利电力职业技术学院学报》2025年第2期39-42,共4页Journal of Guangdong Polytechnic of Water Resources and Electric Engineering

摘　　要：为揭示高吸水性树脂(SAP)对再生混凝土性能的影响规律及作用机制,研究内养护剂掺量、粒径以及再生集料替代率的水泥混凝土收缩和抗裂性能。结果表明:再生混凝土收缩率削减效果与再生集料替代率、内养护剂掺量和粒径密切相关;100%替代率下,早期(1 d)和长龄期(60 d)自收缩率分别降低53~118%、36.2~78.5%;且0.1~0.3%的内养护剂可将90 d自收缩降低33.4~54.1%;内养护剂粒径对收缩的影响与再生集料替代率密切相关,60目内养护剂可将90 d自收缩率提高45%以上。快速平板法试验结果表明,0.2%的内养护掺量可达到最佳抗裂效果,开裂面积抑制率达73.9%。To reveal the influence and mechanism of superabsorbent polymer(SAP)on the performance of recycled concrete,this study investigates the effects of internal curing agent dosage,particle size,and recycled aggregate replacement rate on the shrinkage and crack resistance of cement concrete.The results show that the shrinkage reduction effect of recycled concrete is closely related to the recycled aggregate replacement rate,internal curing agent dosage,and particle size.At a 100%replacement rate,the early-stage(1 day)and long-term(60 days)autogenous shrinkage rates decreased by 53-118%and 36.2-78.5%,respectively.Additionally,an internal curing agent dosage of 0.1-0.3%reduced the 90-day autogenous shrinkage by 33.4-54.1%.The effect of particle size on shrinkage is closely related to the recycled aggregate replacement rate,with 60-mesh internal curing agents increasing the 90-day autogenous shrinkage rate by more than 45%.The rapid flat-panel test results indicate that an internal curing agent dosage of 0.2%achieves the best crack resistance,with a crack area suppression rate of 73.9%.

关 键 词：混凝土 再生集料 内养护 收缩 抗裂 

分 类 号：TU528[建筑科学—建筑技术科学]