化学溶液预处理再生粗骨料对再生混凝土改性的影响

摘要/Abstract

摘要： 为研究不同浓度的硅酸钠溶液和硅烷溶液复合改性再生粗骨料对再生混凝土力学与变形性能及微观结构的影响,通过立方体抗压强度试验研究复合改性对再生混凝土力学性能的影响,同时基于数字图像相关(DIC)方法研究复合改性对再生混凝土变形性能的影响,并借助扫描电子显微镜(SEM)和能谱仪(EDS)微观测试方法分析改性再生混凝土内部微观结构。结果表明:质量分数为5%的硅酸钠溶液和质量分数为10%的硅烷溶液改性后的再生粗骨料24 h吸水率降幅最大,由其制成的再生混凝土28 d抗压强度显著提高,较未改性再生混凝土提高了35.80%;硅酸钠溶液和硅烷溶液复合改性再生粗骨料可有效减小再生混凝土的变形,应力较大时,可阻止应力过度集中,使再生混凝土整体变形性能较好;此外,还可以改善再生粗骨料表面疏松结构和粗糙程度,加强骨料与砂浆界面过渡区(ITZ)性能,但对于新、旧砂浆ITZ性能的改善不明显。

关键词: 全再生粗骨料混凝土, 硅酸钠, 硅烷偶联剂, 微观结构, 变形性能, 力学性能

Abstract: In order to study the effect of composite modification of recycled coarse aggregate with various concentrations of sodium silicate solution and silane solution on the mechanical and deformation properties, as well as the microstructure of recycled concrete, cubic compressive strength tests were used to investigate the effect of composite modification on the mechanical properties of recycled concrete. Meanwhile, the effect of composite modification on the deformation properties of recycled concrete was studied by using the digital image correlation (DIC) method. Additionally, scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) were utilized to analyze the internal microstructure of the modified recycled concrete. The results show that, the water absorption of recycled coarse aggregate for 24 h decreases the most when it is modified with 5% (mass fraction) of sodium silicate solution and 10% (mass fraction) of silane solution, and the 28 d compressive strength of recycled concrete made from it is significantly improved, which is 35.80% higher than that of unmodified recycled concrete. The composite modification of recycled coarse aggregate with sodium silicate solution and silane solution can effectively reduce the deformation of recycled concrete, and when the stress is high, it can stop the excessive concentration of stress, resulting in improved overall deformation property of recycled concrete. Furthermore, it can improve the surface sparse structure and roughness of recycled coarse aggregate, and strengthen the performance of the interfacial transition zone (ITZ) between aggregate and mortar, but the improvement in ITZ performance of new and old mortar is not evident.

Key words: fully recycled coarse aggregate concrete, sodium silicate, silane coupling agent, microstructure, deformation property, mechanical property

中图分类号:

TU528

王二成, 于莲皓, 姜新佩, 王燕杰. 化学溶液预处理再生粗骨料对再生混凝土改性的影响[J]. 硅酸盐通报, 2022, 41(12): 4310-4317.

WANG Ercheng, YU Lianhao, JIANG Xinpei, WANG Yanjie. Effect of Recycled Coarse Aggregate Pretreated with Chemical Solutions on Modification of Recycled Concrete[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(12): 4310-4317.

参考文献

[1] PART W K, RAMLI M, CHEAH C B. An overview on the influence of various factors on the properties of geopolymer concrete derived from industrial by-products[J]. Construction and Building Materials, 2015, 77: 370-395.
[2] REITERMAN P, HOLČAPEK O, ZOBAL O, et al. Freeze-thaw resistance of cement screed with various supplementary cementitious materials[J]. Reviews on Advanced Materials Science, 2019, 58(1): 66-74.
[3] XU Z, HUANG Z P, LIU C J, et al. Research progress on mechanical properties of geopolymer recycled aggregate concrete[J]. Reviews on Advanced Materials Science, 2021, 60(1): 158-172.
[4] PRASAD D, SINGH B, SUMAN S K. Utilization of recycled concrete aggregate in bituminous mixtures: a comprehensive review[J]. Construction and Building Materials, 2022, 326: 126859.
[5] OHEMENG E A, EKOLU S O, QUAINOO H, et al. Model for predicting compressive strength and elastic modulus of recycled concrete made with treated coarse aggregate: empirical approach[J]. Construction and Building Materials, 2022, 320: 126240.
[6] PICCINALI A, DIOTTI A, PLIZZARI G, et al. Impact of recycled aggregate on the mechanical and environmental properties of concrete: a review[J]. Materials (Basel, Switzerland), 2022, 15(5): 1818.
[7] 肖建庄,马旭伟,刘琼,等.全再生混凝土概念的衍化与研究进展[J].建筑科学与工程学报,2021,38(2):1-15.
XIAO J Z, MA X W, LIU Q, et al. Evolvement and research progress of concept for full recycled concrete[J]. Journal of Architecture and Civil Engineering, 2021, 38(2): 1-15 (in Chinese).
[8] 李恒,郭庆军,王家滨,等.再生混凝土界面结构及耐久性综述[J].材料导报,2020,34(13):13050-13057.
LI H, GUO Q J, WANG J B, et al. Meso-/micro-structure of interfacial transition zone and durability of recycled aggregate concrete: a review[J]. Materials Reports, 2020, 34(13): 13050-13057 (in Chinese).
[9] 曹万林,赵羽习,叶涛萍.再生混凝土结构长期工作性能研究进展[J].哈尔滨工业大学学报,2019,51(6):1-17.
CAO W L, ZHAO Y X, YE T P. A review of recent advances in the long-term working characteristic of recycled concrete structure[J]. Journal of Harbin Institute of Technology, 2019, 51(6): 1-17 (in Chinese).
[10] ZHANG H R, JI T, LIU H. Performance evolution of the interfacial transition zone (ITZ) in recycled aggregate concrete under external sulfate attacks and dry-wet cycling[J]. Construction and Building Materials, 2019, 229: 116938.
[11] KIM J. Influence of quality of recycled aggregates on the mechanical properties of recycled aggregate concretes: an overview[J]. Construction and Building Materials, 2022, 328: 127071.
[12] COBAN H S, CETIN B, CEYLAN H, et al. Evaluation of engineering properties of recycled aggregates and preliminary performance of recycled aggregate base layers[J]. Journal of Materials in Civil Engineering, 2022, 34(5): 04022053.
[13] UPSHAW M, CAI C S. Critical review of recycled aggregate concrete properties, improvements, and numerical models[J]. Journal of Materials in Civil Engineering, 2020, 32(11): 03120005.
[14] 宋学锋,白超.化学强化剂对再生骨料及再生混凝土性能的影响研究[J].硅酸盐通报,2019,38(6):1748-1754.
SONG X F, BAI C. Effect of chemical enhancing agents on the properties of recycled aggregate and recycled concrete[J]. Bulletin of the Chinese Ceramic Society, 2019, 38(6): 1748-1754 (in Chinese).
[15] 范玉辉,牛海成,张向冈.纳米SiO₂改性再生混凝土试验研究[J].混凝土,2017(7):92-95.
FAN Y H, NIU H C, ZHANG X G. Experimental study on the modification of recycled aggregate concrete by nano-SiO₂[J]. Concrete, 2017(7): 92-95 (in Chinese).
[16] 朱亚光,徐培蓁.硅烷与PVA对再生混凝土粗骨料改性试验研究[J].混凝土,2015(3):93-95+101.
ZHU Y G, XU P Z. Experimental research on modified of recycled aggregate concrete by silane and PVA[J]. Concrete, 2015(3): 93-95+101 (in Chinese).
[17] 李秋义,韩帅,莫建,等.物理化学强化对再生混凝土抗氯离子渗透性能的影响[J].材料科学与工程学报,2016,34(3):432-436+459.
LI Q Y, HAN S, MO J, et al. Influence of physical and chemical enhancement of recycled coarse aggregate on coefficient of chloride migration of recycled concrete[J]. Journal of Materials Science and Engineering, 2016, 34(3): 432-436+459 (in Chinese).
[18] 时金娜,赵燕茹,郝松,等.基于DIC技术的高温后混凝土变形性能[J].建筑材料学报,2019,22(4):584-591.
SHI J N, ZHAO Y R, HAO S, et al. Deformation behavior of concrete under uniaxial compression after high temperature by DIC technology[J]. Journal of Building Materials, 2019, 22(4): 584-591 (in Chinese).
[19] ZHAO Y R, WANG L, LEI Z K, et al. Study on bending damage and failure of basalt fiber reinforced concrete under freeze-thaw cycles[J]. Construction and Building Materials, 2018, 163: 460-470.
[20] HUANG Y J, HE X J, WANG Q, et al. Deformation field and crack analyses of concrete using digital image correlation method[J]. Frontiers of Structural and Civil Engineering, 2019, 13(5): 1183-1199.
[21] WU Z M, RONG H, ZHENG J J, et al. An experimental investigation on the FPZ properties in concrete using digital image correlation technique[J]. Engineering Fracture Mechanics, 2011, 78(17): 2978-2990.
[22] 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.
[23] PANG B, ZHOU Z H, CHENG X, et al. ITZ properties of concrete with carbonated steel slag aggregate in salty freeze-thaw environment[J]. Construction and Building Materials, 2016, 114: 162-171.
[24] WANG L, ZHENG D, ZHANG S, et al. Effect of nano-SiO₂ on the hydration and microstructure of Portland cement[J]. Nanomaterials (Basel, Switzerland), 2016, 6(12): E241.
[25] WU K, SHI H S, XU L L, et al. Microstructural characterization of ITZ in blended cement concretes and its relation to transport properties[J]. Cement and Concrete Research, 2016, 79: 243-256.