提升抗冻融性能的再生混凝土机械增压养护  

MECHANICAL PRESSURIZATION CURING OF RECYCLED CONCRETE TO IMPROVE ITS FREEZE-THAW RESISTANCE

作　　者：唐超 张露 刘荣 阳辉 匡光阳 TANG Chao;ZHANG Lu;LIU Rong;YANG Hui;KUANG Guangyang(Chengdu Tiantou Industrial Co.,Ltd.,Chengdu 610218,China;School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Chengdu Construction Engineering Group Co.,Ltd.,Chengdu 610031,China;Sichuan Kangli Project Management Co.,Ltd.,Chengdu 610000,China)

机构地区：[1]成都天投实业有限公司,成都610218 [2]重庆交通大学土木工程学院,重庆400074 [3]成都建工集团有限公司,成都610031 [4]康立时代建设集团有限公司,成都610000

出　　处：《低温建筑技术》2023年第12期29-32,共4页Low Temperature Architecture Technology

基　　金：国家自然科学基金项目(51878610);四川省区域创新合作项目(2022YFQ0048)

摘　　要：研究针对因骨料表面旧砂浆附着导致的再生骨料混凝土劣化问题,旨在提出一种在混凝土养护期内通过施加持续压力改善再生混凝土孔结构的成型工艺。对再生混凝土的孔结构进行相关测试,并评估工艺作用下再生混凝土抗冻融性能。结果表明相比没有施加机械力的试件,10MPa压力成型试件的含气量降低54.0%,气泡平均半径减小33.3%,气泡间距系数减小4.8%,进而表现为冻融循环150次时,质量损失率仅为对比组的1/3,显著提升了抗冻融性能。研究成果可为再生混凝土制备预制构件的抗冻融性能提升提供技术支持。This study addresses the deterioration of recycled aggregate concrete due to the adhesion of old mortar on the aggregate surface and aims to propose a molding process to improve the pore structure of recycled concrete by ap⁃plying continuous pressure during the concrete curing period.Tests related to the pore structure of recycled concrete are conducted and the freeze-thaw resistance of recycled concrete under the action of this process is evaluated.The results show that comparing to the specimens without mechanical pressurization,the gas content of the 10MPa pres⁃sure formed specimens decreased by 54.0%,the average radius of bubbles decreased by 33.3%,and the bubble spacing coefficient decreased by 4.8%.This is further demonstrated by a mass loss rate of only 1/3 of the control group when it is subject to 150 freeze-thaw cycles.This novel process significantly improves the freeze-thaw resis⁃tance performance.The results may provide technical support for improving the freeze-thaw resistance of prefabricat⁃ed components made of recycled concrete.

关 键 词：再生混凝土 质量损失率 抗冻融性 

分 类 号：TU578.06[建筑科学—建筑技术科学]