Journal of South China University of Technology(Natural Science) >
Creep Behavior of Reinforced and Unreinforced Recycled Lump/Aggregate Concrete
Received date: 2022-01-27
Online published: 2022-03-11
Supported by
the Key-Area Research and Development Program of Guangdong Province(2019B111107003);the National Natural Science Foundation of China(52078219)
Compressive creep tests on thirty-seven recycled lump/aggregate concrete (RLAC) specimens were carried out to reveal the creep behavior of RLAC by taking the replacement ratio of demolished concrete lumps (DCLs), replacement ratio of recycled coarse aggregates (RCAs), replacement ratio of recycled sand rooted from alluvial-proluvial (A-P) soil, stress level and reinforcement ratio as parameters. The results show that the specific creep of reinforced/unreinforced RLAC is greater than that of reinforced/unreinforced recycled aggregate concrete (RAC). The increase rate of RLAC is 10.1% when unreinforced and the increase rate is 13.4% and 11.5% when the reinforcement ratio is 1.16% and 1.57%, respectively As the replacement ratio of RCAs in new concrete increased from 30% to 50%, the specific creep of reinforced/unreinforced RLAC increased by 7.4% and 11.4% respectively; when the fine aggregate (i.e., river sand) of new concrete is completely replaced by the recycled sand from A-P soil, the creep behavior of reinforced/unreinforced RLAC shows almost no change, but both of the shrinkage deformation decreased. As the reinforcement ratio increases from 1.16% to 1.57%, the specific creep of RLAC and RAC decrease by 5.0% and 6.6%, respectively. Reinforcement reduces the shrinkage deformation of RAC and RLAC, and the reduction grows with the increase of reinforcement ratio. As the replacement ratio of RCAs in new concrete increased from 30% to 50%, the elastic modulus of RLAC have little change and it is also almost free from the impact of replacing the fine aggregate (i.e., river sand) of new concrete with the recycled sand from A-P soil; and when the stress level is less than 0.4, the specific creep of RLAC is nearly deemed as irrelevant to the stress level.
WU Bo, CHEN Zhaonan, WANG Hui . Creep Behavior of Reinforced and Unreinforced Recycled Lump/Aggregate Concrete[J]. Journal of South China University of Technology(Natural Science), 2022 , 50(7) : 35 -42 . DOI: 10.12141/j.issn.1000-565X.220046
| 1 | JIAN S M, WU B .Compressive behavior of compound concrete containing demolished concrete lumps and recycled aggregate concrete[J].Construction and Building Materials,2021,272:121624. |
| 2 | 肖建庄,许向东,范玉辉 .再生混凝土收缩徐变试验及徐变神经网络预测[J].建筑材料学报,2013,16(5):752-757. |
| 2 | XIAO Jianzhuang, XU Xiangdong, FAN Yuhui .Shrinkage and creep of recycled aggregate concrete and their prediction by ANN Method[J].Journal of Building Materials,2013,16(5):752-757. |
| 3 | LYE C Q, DHIR R K, GHATAORA G S,et al .Creep strain of recycled aggregate concrete[J]?.Construction and Building Materials,2016,102:244-259. |
| 4 | 邹超英,王勇,胡琼 .再生混凝土徐变度试验研究及模型预测[J].武汉理工大学学报,2009,31(12):94-98. |
| 4 | ZOU Chaoying, WANG Yong, HU Qiong .Experimental study and model predictive of recycled aggregate concrete creep[J].Journal of Wuhan University of Technology,2009,31(12):94-98. |
| 5 | 白国良,祁豪,刘超 .再生混凝土徐变试验与预测模型研究[J].建筑结构学报,2016,37(S2):121-126. |
| 5 | BAI Guoliang, QI Hao, LIU Chao .Study on creep test and prediction model of recycled aggregate concrete[J].Journal of Building Structures,2016,37(S2):121-126. |
| 6 | TAM V W Y, KOTRAYOTHAR D, XIAO J Z .Long-term deformation behaviour of recycled aggregate concrete[J].Construction and Building Materials,2015,100(5):262-272. |
| 7 | WU B, LIN L, ZHAO J X,et al .Creep behavior of thin-walled circular steel tubular columns filled with demolished concrete lumps and fresh concrete[J].Construction and Building Materials,2018,187:773-790. |
| 8 | WU B, YU Y, CHEN Z P,et al .Shape effect on compressive mechanical properties of compound concrete containing demolished concrete lumps[J].Construction and Building Materials,2018,187:50-64. |
| 9 | 金属材料拉伸实验 第1部分:室温试验方法: [S].北京:中国标准出版社,2010. |
| 10 | 再生混合混凝土组合结构技术标准: [S].北京:中国建筑工业出版社,2019. |
| 11 | 吴波,张金锁,赵新宇 .薄壁方钢管再生混合短柱轴压性能试验研究[J].建筑结构学报,2012,33(9):30-37. |
| 11 | WU Bo, ZHANG Jinsuo, ZHAO Xinyu .Tests on axial behavior of stub square thin-walled steel tubular columns filled with demolished concrete blocks[J].Journal of Building Structures,2012,33(9):30-37. |
| 12 | 李华,汪洋,王育江,等 .膨胀剂对混凝土早期基本徐变的影响[J].建筑材料学报,2022,25(3):256-262. |
| 12 | LI Hua, WANG Yang, WANG Yujiang,et al .Effect of expansive additives on basic creep of early-age concrete[J].Journal of Building Materials,2022,25(3):256-262. |
| 13 | 严华 .再生混合混凝土及薄壁圆钢管再生混合短柱的轴压徐变性能试验研究[D].广州:华南理工大学,2014. |
| 14 | 吴波,曹慧璇,林朗,等.水泥砂土浆的力学性能试验研究[J].华南理工大学学报(自然科学版),2020,48(5):1-8. |
| 14 | WU Bo, CAO Huixuan, LIN Lang,et al .Experimental study on mechanical behaviors of cement mortar containing excavated soil[J].Journal of South China University of Technology(Natural Science Edition),2020,48(5):1-8. |
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