作者：周金枝¹, 石赐明^1,2, 钟楚珩¹, 付甜甜¹, 赵宏源¹

作者单位：1. 湖北工业大学土木建筑与环境学院，湖北 武汉 430068;
2. 中建三局集团(深圳)有限公司，广东 深圳 518000

关键词：再生混凝土;Na₂O·nSiO₂及PVA改性;Weibull分布;损伤抗性;微观机理

摘要：

为研究再生骨料改性对再生混凝土微观损伤机理的影响，该文用5%硅酸钠溶液（Na₂O·nSiO₂溶液）和10%聚乙烯醇溶液（PVA溶液）对不同级配再生骨料预浸泡进行改性。通过再生混凝土微小单元强度服从Weibull统计分布对抗压强度进行损伤演化分析和扫描电子显微镜（SEM）对骨料和混凝土微观形貌和机理分析。结果表明：经过5%硅酸钠溶液（Na₂O·nSiO₂溶液）和10%聚乙烯醇溶液（PVA溶液）改性后的再生混凝土均能显著提升内部微小单元损伤抗性和微观结构的密实性，且5%硅酸钠溶液（Na₂O·nSiO₂溶液）浸泡改性再生骨料对再生混凝土的提升效果劣于10%聚乙烯醇溶液（PVA溶液）。采用连续级配5~31.5 mm的再生混凝土损伤抗性显著高于单一级配10~16 mm和16~25 mm的再生混凝土损伤抗性。

Analysis of microscopic damage mechanism of Weibull distribution model modified recycled concrete
ZHOU Jinzhi¹, SHI Ciming^1,2, ZHONG Chuheng¹, FU Tiantian¹, ZHAO Hongyuan¹
1. College of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China;
2. China Construction Third Bureau Group (Shenzhen ) Co., Ltd., Shenzhen 518000 , China
Abstract: In order to study the effect of recycled aggregate modification on the microscopic damage mechanism of recycled concrete, 5% sodium silicate solution (Na₂O·nSiO₂ solution) and 10% polyvinyl alcohol solution (PVA solution) were used to modify the pre-soaking of recycled aggregate with different gradations. Damage evolution analysis and scanning electron microscopy (SEM) analysis on the microstructure and mechanism of aggregate and concrete were carried out through the compressive strength of recycled concrete micro-units obeying Weibull statistical distribution. The results show that the recycled concrete modified by 5% sodium silicate solution (Na₂O·nSiO₂ solution) and 10% polyvinyl alcohol solution (PVA solution) can significantly improve the damage resistance of internal micro units and the compactness of microstructure, and the improvement effect of recycled aggregate modified by 5% sodium silicate solution (Na₂O·nSiO₂ solution) on recycled concrete is inferior to that of 10% polyvinyl alcohol solution (PVA solution). The damage resistance of recycled concrete with continuous gradation of 5-31.5 mm is significantly higher than that of recycled concrete with single gradation of 10-16 mm and 16-25 mm.
Keywords: recycled concrete;modification of Na₂O·nSiO₂ and PVA;Weibull distribution;damage resistance;micromechanism
2024, 50(4):125-133  收稿日期: 2022-03-05;收到修改稿日期: 2022-06-01
基金项目: 桥梁结构健康与安全国家重点实验室（BHSKL19-04-KF）；湖北省教研项目（省2017314）；湖北工业大学博士启动基金（BSQD2020051）
作者简介: 周金枝(1964-),女,湖北武汉市人,教授,研究方向为土木工程材料和结构强度设计与仿真。
参考文献
[1] 王雅思, 郑建岚, 游帆. 再生骨料强化方法研究进展[J]. 材料导报, 2021, 35(5): 5053-5061.
WANG Y S, ZHENG J L, YOU F. Review on enhancement methods of recycled aggregate[J]. Materials Reports, 2021, 35(5): 5053-5061.
[2] 盛朝晖, 牛培飞, 游文斐. 多因素对再生混凝土力学性能及抗冻性的影响[J]. 中国测试, 2021, 47(2): 140-148.
SHENG Z H, NIU P F, YOU W. Effect of multiple factors on mechanical properties and frost resistance of recycled concrete[J]. China Measurement & Test, 2021, 47(2): 140-148.
[3] 李秋义, 李云霞, 朱崇绩, 等. 再生混凝土骨料强化技术研究[J]. 混凝土, 2006(1): 75-77.
LI Q Y, LI Y X, ZHU C J, et al. Strengthening technique of recycled concrete aggregate[J]. Concrete, 2006(1): 75-77.
[4] 肖建庄, 吴磊, 范玉辉. 微波加热再生粗骨料改性试验[J]. 混凝土, 2012(7): 55-57.
XIAO J Z, WU L, FAN Y H. Test on modification of recycled coarse aggregate by microwave heating[J]. Concrete, 2012(7): 55-57.
[5] 程海丽, 王彩彦. 水玻璃对混凝土再生骨料的强化试验研究[J]. 新型建筑材料, 2004(12): 12-14.
CHENG H L, WANG C Y. Experimental study on strengthen concrete regenerated aggregate with water glass[J]. New Building Materials, 2004(12): 12-14.
[6] 许佼. 再生混凝土骨料改性研究及其应用[D]. 淮南: 安徽理工大学, 2017.
XU J. Study on modification of recycle concrete aggregate and its application[D]. Huainan: Anhui University of Science and Technology, 2017.
[7] 王瑞骏, 缑彦强, 徐帆. 不同粒径再生粗骨料二级配混凝土力学性能试验研究[J]. 水力发电, 2018, 44(3): 101-105.
WANG R J, GOU Y Q, XU F. Experimental study on mechanical properties of recycled coarse aggregate two-graded concrete with different particle sizes[J]. Water Power, 2018, 44(3): 101-105.
[8] 李琼, 冯琼, 曹辉. 再生骨料级配对混凝土力学性能的影响及微观机理分析[J]. 江苏大学学报(自然科学版), 2019, 40(5): 614-620.
LI Q, FENG Q, CAO H. Effects of recycled aggregates gradation on mechanical performance of concrete and microscopic performance analysis[J]. Journal of Jiangsu University(Natural Science Edition), 2019, 40(5): 614-620.
[9] 唐春安, 朱万成. 混凝土损伤与断裂-数值试验[M]. 北京: 科学出版社, 2003.
[10] 赵吉坤. 混凝土四相复合模型的三维细观破坏模拟[J]. 土木建筑与环境工程, 2009, 31(4): 37-43.
ZHAO J K. 3D meso-scale failure simulation of four-phase composite concrete[J]. Journal of CiviI, Architectural & Environmental Engineering, 2009, 31(4): 37-43.
[11] 龙源, 万文乾, 纪冲, 等. 基于WEIBULL概率分布的钢纤维混凝土材料损伤演化分析[J]. 材料科学与工程学报, 2007, 25(6): 830-832.
LONG Y, WAN W Q, JI C, et al. Study on damage evolvement of steel fiber concrete material by Weibull probability distribution[J]. Journal of Materials Science & Engineer, 2007, 25(6): 830-832.
[12] 杜修力, 金浏. 混凝土材料细观单元弹模非均匀统计特性研究[J]. 工程力学, 2012, 29(10): 106-115.
DU X L, JIN L. Research on the heterogeneous statistical properties of elastic modulus of a concrete meso-scale unit[J]. Engineering Mechanics, 2012, 29(10): 106-115.
[13] OLLIVIER J P, MASO J C, BOURDETTE B. Interfacial transition zone in concrete[J]. Advanced Cement Based Materials, 1995, 2(1): 30-38.
[14] 宋晶颖. 冻融循环与硫酸盐侵蚀耦合作用下纳米SiO₂对混凝土性能影响研究[J]. 中国测试, 2022， 48(11): 174-179.
SONG J Y. Study on the effect of nano-SiO₂ on concrete performance under the combined action of freeze-thaw cycle and sulfate erosion[J]. China Measurement & Test, 2022， 48(11): 174-179.
[15] 张学兵, 方志, 郭雪怡, 等. DSP 强化与预处理的再生骨料混凝土强度及破坏机理分析[J]. 工业建筑, 2012, 42(4): 15-20.
ZHANG X B, FANG Z, GUO X Y, et al. Strength and failure mechanism analysis of recycled aggregate concrete improved by dsp grout[J]. Industrial Construction, 2012, 42(4): 15-20.