摘要
由于再生粗骨料中存在较多微孔隙和微裂缝,导致再生混凝土吸水率高且极易达到冻融破坏的临界水饱和程度,所以再生混凝土抗冻性能较差,严重危害了严寒地区混凝土建筑物的安全性和耐久性。因此,开展再生混凝土抗冻性能的研究对其在严寒地区的应用推广具有重要意义。基于再生混凝土冻融破坏的国内外研究现状,介绍了混凝土冻融破坏机理,综述了再生骨料品质及掺量、水饱和度、孔结构和矿物掺合料等因素对再生混凝土抗冻性能的影响规律及作用机理,进而总结了再生混凝土结构构件抗冻性能的研究,探讨了改善再生混凝土抗冻性能的技术措施,并对现有的再生混凝土冻融损伤预测模型予以总结。基于已有研究发现,针对再生混凝土抗冻性能的研究要以其实际服役环境为背景,从细微观层次揭示其对宏观冻融损伤机理的影响,并分析其微细观尺度影响机理与宏观性能的关联机制,以此来推动严寒地区再生混凝土的实际工程应用。
For severe cold areas,due to more micro-pores and micro-cracks in the recycled coarse aggregate(RCA),the high water absorption rate of recycled aggregate concrete(RAC)can easily reach the critical water saturation level of freezing-thawing damage,resulting in the poor performance in frost resistance,and seriously endanger the safety and durability of concrete buildings.Therefore,the research on frost resistance of RAC is of great significance to its engineering application.Based on the progress of research about the freezing-thawing damage of RAC at home and abroad,the deterioration mechanism of concrete was first introduced.Then,the influences of several factors including the quality and dosages of recycled coarse aggregates,water saturation degree,pore structure and the mineral admixtures on the frost resistance property of RAC were reviewed.Furthermore,the studies on the frost resistance of RAC members were summarized.The technical measures to improve the frost resistance of RAC were further discussed.Finally,the existing prediction models of freezing-thawing damage for RAC were summarized.Aiming at promoting the practical engineering application of recycled concrete in cold regions,the research on the frost resistance of RAC should be based on its actual service environment to reveal its influence on the macroscopic freezing-thawing damage mechanism from meso and micro level,and analyze the correlation mechanism between the meso-and microscale and the macro-scale.
作者
鲍玖文
于子浩
张鹏
李树国
赵铁军
BAO Jiuwen;YU Zihao;ZHANG Peng;LI Shuguo;ZHAO Tiejun(Department of Civil Engineering,Qingdao University of Technology,Qingdao 266033,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2022年第4期142-157,共16页
Journal of Building Structures
基金
国家自然科学基金项目(51922052,51778309,51908307)
山东省自然科学基金项目(ZR2018JL018)。
关键词
再生混凝土
抗冻性
水饱和度
冻融损伤模型
recycled aggregate concrete
frost resistance property
water saturation degree
freezing-thawing damage model
