矿物掺合料对再生混凝土抗冻性与可再生性的影响

摘要/Abstract

摘要： 为探究矿物掺合料对再生混凝土抗冻性与可再生性的影响,本文选取硅灰、粉煤灰和粒化高炉矿渣三种矿物掺和料,通过不同掺量组合制备了五组不同胶凝体系的再生混凝土。采用快冻法对再生混凝土进行冻融试验,通过测定冻融过程中再生混凝土的相对动弹性模量、质量损失率和抗压强度损失率评价其抗冻性,采用SEM观察冻融后再生混凝土的微观结构。此外,对冻融后的再生混凝土进行破碎,获得二代再生粗骨料,并依据其表观密度、压碎值、坚固值和吸水率评估再生混凝土的可再生性。结果表明:5%(质量分数,下同)硅灰+20%粉煤灰+20%矿渣+55%水泥组合的质量损失率和抗压强度损失率明显比单掺5%硅灰以及5%硅灰+20%粉煤灰和5%硅灰+20%矿渣组合的低,且相对动弹性模量比其他组合的高。四种不同胶凝体系的二代再生粗骨料物理性能均达Ⅲ类标准,可用于强度等级为C25的结构混凝土的制备。

关键词: 再生混凝土, 再生粗骨料, 矿物掺合料, 抗冻性, 可再生性

Abstract: In order to explore the effects of mineral admixtures on frost resistance and renewability of recycled concrete, three kinds of mineral admixtures, such as silica fume fly ash, fly ash silica fume and granulated blast furnace slag, were selected. Five groups of recycled aggregate concrete with different cementitious systems were prepared by different dosage combinations. The freeze-thaw test of recycled aggregate concrete was carried out by rapid freezing method. By measuring the relative dynamic elastic modulus, mass loss rate and compressive strength loss rate of recycled aggregate concrete during the freeze-thaw process, the frost resistance of recycled aggregate concrete with different cementitious systems was evaluated. The microstructure of recycled aggregate concrete after freeze-thaw cycle was observed by SEM. In addition, the recycled aggregate concrete after freeze-thaw cycle was crushed to obtain the second generation of recycled coarse aggregate, and the renewability of recycled aggregate concrete was evaluated according to its apparent density, crushing value, firmness value and water absorption. The results show that the mass loss rate and compressive strength loss rate of combination of 5% (mass fraction, the same below)silica fume +20% fly ash +20% slag +55% cement are significantly lower than those of combination of 5% silica fume, 5% silica fume +20% fly ash and 5% silica fume +20% slag, and the relative dynamic elastic modulus is also higher than that of other combinations. The second generation of recycled coarse aggregates of four combinations all meet the grade Ⅲ aggregate standard, which can be reused for structural concrete with strength grade of C25.

Key words: recycled aggregate concrete, recycled coarse aggregate, mineral admixture, frost resistance, renewability

中图分类号:

TU528.01

成旭, 朱平华, 王新杰, 刘惠, 王华宇, 王月盈, 陈垂睿. 矿物掺合料对再生混凝土抗冻性与可再生性的影响[J]. 硅酸盐通报, 2024, 43(3): 956-964.

CHENG Xu, ZHU Pinghua, WANG Xinjie, LIU Hui, WANG Huayu, WANG Yueying, CHEN Chuirui. Effects of Mineral Admixtures on Frost Resistance and Renewability of Recycled Aggregate Concrete[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2024, 43(3): 956-964.

参考文献

[1] DONG J F, WANG Q Y, GUAN Z W. Structural behaviour of recycled aggregate concrete filled steel tube columns strengthened by CFRP[J]. Engineering Structures, 2013, 48: 532-542.
[2] XIAO J Z, LI W G, FAN Y H, et al. An overview of study on recycled aggregate concrete in China (1996-2011)[J]. Construction and Building Materials, 2012, 31: 364-383.
[3] 杨冬鹏, 郭卫民, 王宝民. 基于Weibull模型的混凝土冻融损伤寿命预测及应用[J]. 水利学报, 2022, 53(8): 977-983.
YANG D P, GUO W M, WANG B M. Prediction and application of freezing-thawing damage life of concrete based on Weibull model[J]. Journal of Hydraulic Engineering, 2022, 53(8): 977-983 (in Chinese).
[4] 侯泽宇, 李子昂, 王家滨, 等. 多掺矿物掺合料再生混凝土力学性能研究[J]. 混凝土, 2023(1): 58-63.
HOU Z Y, LI Z A, WANG J B, et al. Study on mechanical properties of recycled concrete mixed with fly ash-silica fume-metakaolin-blast slag[J]. Concrete, 2023(1): 58-63 (in Chinese).
[5] TRAN D L, MOURET M, CASSAGNABÈRE F, et al. Effects of intrinsic granular porosity and mineral admixtures on durability and transport properties of recycled aggregate concretes[J]. Materials Today Communications, 2022, 33: 104709.
[6] GAO S, JI Y, QIN Z W, et al. A comprehensive analysis of pore structures and performances of mineral admixtures modified recycled aggregate concrete based on experiment and theory[J]. Construction and Building Materials, 2022, 358: 129451.
[7] KOU S C, POON C S, AGRELA F. Comparisons of natural and recycled aggregate concretes prepared with the addition of different mineral admixtures[J]. Cement and Concrete Composites, 2011, 33(8): 788-795.
[8] 余舟, 杨华全, 王磊, 等. 粉煤灰品质对混凝土性能影响试验研究[J]. 混凝土, 2019(12): 80-83.
YU Z, YANG H Q, WANG L, et al. Study on effect of quality of fly ash on concrete performance[J]. Concrete, 2019(12): 80-83 (in Chinese).
[9] 丁向群, 周睿彤, 王钰. 硅灰对混凝土抗冻性能及其孔结构的影响[J]. 混凝土, 2017(2): 53-55.
DING X Q, ZHOU R T, WANG Y. Effect of silica fume on the frost resistance and pore structure of concrete[J]. Concrete, 2017(2): 53-55 (in Chinese).
[10] 覃银辉, 邓寿昌, 张学兵. 掺外加剂的再生混凝土抗冻性能研究[J]. 湘潭大学自然科学学报, 2006, 28(3): 117-121.
QIN Y H, DENG S C, ZHANG X B. Frost resistance of recycled concrete with antifreeze[J]. Natural Science Journal of Xiangtan University, 2006, 28(3): 117-121 (in Chinese).
[11] 黄显智, 王子明, 姜德义. 再生集料混凝土循环利用的试验研究[J]. 混凝土, 2003(10): 24-27.
HUANG X Z, WANG Z M, JIANG D Y. Experimental study on recycling of recycled aggregate concrete[J]. Concrete, 2003(10): 24-27 (in Chinese).
[12] THOMAS C, DE BRITO J, GIL V, et al. Multiple recycled aggregate properties analysed by X-ray microtomography[J]. Construction and Building Materials, 2018, 166: 171-180.
[13] 吕寅杰, 谢政, 郭丽. 废弃混凝土重生与再利用的探讨[J]. 四川建材, 2016, 42(7): 12+14.
LYU Y J, XIE Z, GUO L. Discussion on regeneration and reuse of waste concrete[J]. Sichuan Building Materials, 2016, 42(7): 12+14 (in Chinese).
[14] 陈建奎, 王栋民. 高性能混凝土(HPC)配合比设计新法: 全计算法[J]. 硅酸盐学报, 2000, 28(2): 194-198.
CHEN J K, WANG D M. New mix design method for HPC: overall calculation method[J]. Journal of the Chinese Ceramic Society, 2000, 28(2): 194-198 (in Chinese).
[15] TAM V W Y, TAM C M. Assessment of durability of recycled aggregate concrete produced by two-stage mixing approach[J]. Journal of Materials Science, 2007, 42(10): 3592-3602.
[16] 中华人民共和国住房和城乡建设部, 国家市场监督管理总局. 混凝土物理力学性能试验方法标准: GB/T 50081—2019[S]. 北京: 中国建筑工业出版社, 2019.
Ministry of Housing and Urban-Rural Development of the People's Republic of China, State Administration for Market Supervision and Administration. Standards for test methods of physical and mechanical properties of concrete: GB/T 50081—2019[S]. Beijing: China Construction Industry Publishing House, 2019 (in Chinese).
[17] 中华人民共和国住房和城乡建设部. 普通混凝土长期性能和耐久性能试验方法标准: GB/T 50082—2009[S]. 北京: 中国建筑工业出版社, 2009.
Ministry of Housing and Urban-Rural Development of the People's Republic of China. Standard for test methods of long-term performance and durability of ordinary concrete: GB/T 50082—2009[S]. Beijing: China Building Industry Press, 2009 (in Chinese).
[18] 国家质量监督检验检疫总局, 中国国家标准化管理委员会. 混凝土用再生粗骨料: GB/T 25177—2010[S]. 北京: 中国标准出版社, 2011.
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, National Standardization Administration of China. Recycled coarse aggregate for concrete: GB/T 25177—2010[S]. Beijing: China Standards Publishing House, 2011 (in Chinese).
[19] 中华人民共和国住房和城乡建设部. 再生骨料应用技术规程: JGJ/T 240—2011[S]. 北京: 中国建筑工业出版社, 2011.
Ministry of Housing and Urban-Rural Development of the People's Republic of China. Technical specification for application of recycled aggregate: JGJ/T 240—2011[S]. Beijing: China Construction Industry Press, 2011 (in Chinese).
[20] 朱平华, 张苏承. 弯曲荷载作用下循环再生混凝土抗冻性研究[J]. 混凝土, 2016(1): 84-87.
ZHU P H, ZHANG S C. Frost resistance of circular recycled aggregate concrete under bending load[J]. Concrete, 2016(1): 84-87 (in Chinese).
[21] 魏达, 朱平华, 王新杰, 等. 再生粗骨料附着砂浆含量对再生混凝土抗冻耐久性的影响[J]. 硅酸盐通报, 2021, 40(3): 765-774.
WEI D, ZHU P H, WANG X J, et al. Effect of attached mortar content of recycled coarse aggregate on frost resistance durability of recycled aggregate concrete[J]. Bulletin of the Chinese Ceramic Society, 2021, 40(3): 765-774 (in Chinese).
[22] 王安岭, 段遵莉, 杨玉根, 等. 复合矿渣掺合料高性能混凝土的研究与应用[J]. 施工技术, 2005, 34(4): 24-26.
WANG A L, DUAN Z L, YANG Y G, et al. Study and application of compound cinder blending material high performance concrete[J]. Construction Technology, 2005, 34(4): 24-26 (in Chinese).
[23] FENG J C, ZONG N W, ZHU P H, et al. The frost-resisting durability of high strength self-compacting pervious concrete in deicing salt environment[J]. Journal of Wuhan University of Technology Materials Science Edition, 2020, 35(1): 167-175.
[24] 陈爱玖, 孙晓培, 张敏, 等. 活性掺合料再生混凝土抗冻性能试验[J]. 混凝土, 2014(6): 20-23.
CHEN A J, SUN X P, ZHANG M, et al. Experiment on the frost resistance of active admixture recycled concrete[J]. Concrete, 2014(6): 20-23 (in Chinese).