纤维对再生砖混ECC力学性能及微观结构的影响

摘要/Abstract

摘要： 为促进不同粒径再生砖混骨料的多元化利用,本试验采用再生砖混细骨料完全代替石英砂,采用不同掺量聚丙烯纤维制备再生砖混工程水泥基复合材料(ECC),研究其受力破坏特征、强度影响机理及微观结构对力学性能的影响。结果表明:未掺纤维的再生砖混ECC的失效模式为脆性破坏,而掺纤维的再生砖混ECC受拉时具有明显的应变硬化特征,随着纤维掺量的增加,其抗折强度、极限抗拉强度和极限拉应变持续增大,抗压强度呈先增大后减小趋势,表现出良好的延性和韧性破坏特征;再生砖混ECC的孔隙率在11.28%~13.68%,通过SEM观察,发现纤维与再生砖混ECC黏结性能较好,纤维破坏模式主要为拔出和拉断破坏,开裂后应变硬化拉伸幅度和拉伸强度低于普通ECC混凝土;新旧浆体界面黏结性能相对薄弱,破坏时微裂缝容易在界面过渡区产生和发展。

关键词: 再生砖混细骨料, 工程水泥基复合材料, 应变硬化, 聚丙烯纤维, 纤维掺量, 力学性能, 微观结构

Abstract: In order to promote the diversified utilization of recycled brick concrete aggregate with different particle sizes, recycled brick concrete fine aggregate was used to completely replace quartz sand, and mixed with different content of polypropylene fiber to prepare recycled brick concrete engineering cementitious composites (ECC). The effects of failure characteristics, strength influence mechanism and microstructure on mechanical properties were studied. The results show that the failure mode of specimens without fiber is brittle failure, and recycled brick concrete ECC with fiber has obvious strain hardening characteristics during tensile stress. With the increase of fiber content, the flexural strength, ultimate tensile strength and ultimate tensile strain of recycled brick concrete ECC continue to increase, and the compressive strength increases first and then decreases, which shows good ductility and ductile failure characteristics. The porosity of recycled brick concrete ECC is 11.28%~13.68%. Fiber has good bonding property with recycled brick concrete ECC observed by SEM, the fiber failure modes are mainly pull-out and tensile failure, and the strain hardening tensile amplitude and tensile strength after cracking are lower than that of ordinary ECC concrete. The interface bonding property of old and new mortar is relatively weak, and micro-cracks are easy to occur and develop in the interface transition zone during failure.

Key words: recycled brick concrete fine aggregate, engineered cementitious composites, strain hardening, polypropylene fiber, fiber content, mechanical property, microstructure

中图分类号:

TU528

王磊, 尹梦环, 张继旺, 周靖鸿, 李佳, 刘岩, 李泉. 纤维对再生砖混ECC力学性能及微观结构的影响[J]. 硅酸盐通报, 2023, 42(10): 3479-3488.

WANG Lei, YIN Menghuan, ZHANG Jiwang, ZHOU Jinghong, LI Jia, LIU Yan, LI Quan. Effect of Fiber on Mechanical Properties and Microstructure of Recycled Brick Concrete ECC[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(10): 3479-3488.

参考文献

[1] 马昆林, 黄新宇, 胡明文, 等. 砖混再生粗骨料混凝土力学性能及工程应用研究[J]. 硅酸盐通报, 2020, 39(8): 2600-2607.
MA K L, HUANG X Y, HU M W, et al. Mechanical properties and engineering application of brick-concrete recycled coarse aggregate concrete[J]. Bulletin of the Chinese Ceramic Society, 2020, 39(8): 2600-2607 (in Chinese).
[2] 冯为为. 资源化利用破解建筑垃圾处理难题[J]. 节能与环保, 2018(10): 34-36.
FENG W W. Resource utilization to solve the problem of construction waste treatment[J]. Energy Conservation & Environmental Protection, 2018(10): 34-36 (in Chinese).
[3] TAM V W Y, SOOMRO M, EVANGELISTA A C J. A review of recycled aggregate in concrete applications (2000-2017)[J]. Construction and Building Materials, 2018, 172: 272-292.
[4] 肖建庄, 张航华, 唐宇翔, 等. 废弃混凝土再生原理与再生混凝土基本问题[J]. 科学通报, 2023, 68(5): 510-523.
XIAO J Z, ZHANG H H, TANG Y X, et al. Recycling principle of waste concrete and basic problems of recycled concrete[J]. Chinese Science Bulletin, 2023, 68(5): 510-523 (in Chinese).
[5] NILI M, SASANIPOUR H, ASLANI F. The effect of fine and coarse recycled aggregates on fresh and mechanical properties of self-compacting concrete[J]. Materials, 2019, 12(7): 1120.
[6] EVANGELISTA L, DE-BRITO J. Mechanical behaviour of concrete made with fine recycled concrete aggregates[J]. Cement and Concrete Composites, 2007, 29(5): 397-401.
[7] LIANG J F, WANG E, ZHOU X, et al. Influence of high temperature on mechanical properties of concrete containing recycled fine aggregate[J]. Computers & Concrete, 2018, 21(1): 87-94.
[8] 曹明莉, 许玲, 张聪. 高延性纤维增强水泥基复合材料的微观力学设计、性能及发展趋势[J]. 硅酸盐学报, 2015, 43(5): 632-642.
CAO M L, XU L, ZHANG C. Review on micromechanical design, performance and development tendency of engineered cementitious composite[J]. Journal of the Chinese Ceramic Society, 2015, 43(5): 632-642 (in Chinese).
[9] 元成方, HARIS S, 楚留声, 等. 生态型超高韧性水泥基复合材料力学性能试验研究[J]. 新型建筑材料, 2021, 48(6): 6-10.
YUAN C F, HARIS S, CHU L S, et al. Experimental study on mechanical properties of ecological engineered cementitious composites[J]. New Building Materials, 2021, 48(6): 6-10 (in Chinese).
[10] GAO D Y, LV M Y, YANG L, et al. Experimental study of utilizing recycled fine aggregate for the preparation of high ductility cementitious composites[J]. Materials, 2020, 13(3): 679.
[11] HUAN Y J, WEI W J, JIN Y. Experimental study on FRP-reinforced PP ECC beams under reverse cyclic loading[J]. Mechanics of Composite Materials, 2014, 50(4): 447-456.
[12] DANG J T, ZHAO J, PANG S D, et al. Durability and microstructural properties of concrete with recycled brick as fine aggregates[J]. Construction and Building Materials, 2020, 262: 120032.
[13] ABADI M S B, AKBARI M. Evaluation of mechanical properties of fiber reinforced recycled concrete: effect of size and amount of recycled aggregate, type and amount of fibers[J]. Journal of Structural Engineering, 2017, 4(1): 138e50.
[14] KIM H D, YOO J S, Kim M H, et al. The fiber reinforcing effect on the physical properties of recycled fine aggregate concrete[J]. Textile Science and Engineering, 2008, 45(1): 47-56.
[15] 辛志鹏, 朱亚光, 徐培蓁, 等. 粉煤灰及聚丙烯纤维对再生透水混凝土性能的影响[J]. 混凝土, 2023(1): 73-77+81.
XIN Z P, ZHU Y G, XU P Z, et al. Influence of fly ash and polypropylene fiber on properties of recycled permeable concrete[J]. Concrete, 2023(1): 73-77+81 (in Chinese).
[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 of Market Supervision and Administration. Standard for test methods of physical and mechanical properties of concrete: GB/T 50081—2019[S]. Beijing: China Construction Industry Press, 2019 (in Chinese).
[17] 工业和信息化部. 高延性纤维增强水泥基复合材料力学性能试验方法: JC/T 2461—2018[S]. 北京: 建材工业出版社, 2018.
Ministry of Industry and Information Technology. Test method for mechanical properties of high ductility fiber reinforced cement-based composites: JC/T 2461—2018[S]. Beijing: Building Materials Industry Press, 2018 (in Chinese).
[18] 史才军, 何稳, 吴泽媚, 等. 纤维对UHPC力学性能的影响研究进展[J]. 硅酸盐通报, 2015, 34(8): 2227-2236+2247.
SHI C J, HE W, WU Z M, et al. Influence of fibers on mechanical properties of UHPC[J]. Bulletin of the Chinese Ceramic Society, 2015, 34(8): 2227-2236+2247 (in Chinese).
[19] 王磊, 熊祖菁, 刘存鹏, 等. 掺入聚丙烯纤维珊瑚混凝土的力学性能研究[J]. 混凝土, 2014(7): 96-99.
WANG L, XIONG Z J, LIU C P, et al. Mechanical property tests of coral concerete with polypropylene fiber[J]. Concrete, 2014(7): 96-99 (in Chinese).
[20] 王晶. 高延性水泥基复合材料力学性能试验研究[D]. 西安: 西安建筑科技大学, 2013.
WANG J. Experimental study on mechanical properties of high ductility cement-based composites[D]. Xi’an: Xi’an University of Architecture and Technology, 2013 (in Chinese).
[21] ŞAHMARAN M, LI V C. De-icing salt scaling resistance of mechanically loaded engineered cementitious composites[J]. Cement and Concrete Research, 2007, 37(7): 1035-1046.
[22] 高秀梅, 刘曙光, 闫敏. 冻融循环后PVA-ECC拉伸性能衰减规律研究[J]. 硅酸盐通报, 2023, 42(3): 837-844.
GAO X M, LIU S G, YAN M. Attenuation law of tensile property of PVA-ECC after freezing-thawing cycles[J]. Bulletin of the Chinese Ceramic Society, 2023, 42(3): 837-844 (in Chinese).
[23] 刘超, 余伟航, 刘化威, 等. 再生砖骨料混凝土力学性能及破坏机理研究[J]. 材料导报, 2021, 35(13): 13025-13031.
LIU C, YU W H, LIU H W, et al. Study on mechanical properties and failure mechanism of recycled brick aggregate concrete[J]. Materials Reports, 2021, 35(13): 13025-13031 (in Chinese).
[24] POON C S, SHUI Z H, LAM L. Effect of microstructure of ITZ on compressive strength of concrete prepared with recycled aggregates[J]. Construction and Building Materials, 2004, 18(6): 461-468.
[25] ŞAHMARAN M, ÖZBAY E, YÜCEL H E, et al. Effect of fly ash and PVA fiber on microstructural damage and residual properties of engineered cementitious composites exposed to high temperatures[J]. Journal of Materials in Civil Engineering, 2011, 23(12): 1735-1745.
[26] LUO J J, CAI Z W, YU K Q, et al. Temperature impact on the micro-structures and mechanical properties of high-strength engineered cementitious composites[J]. Construction and Building Materials, 2019, 226: 686-698.
[27] SUN R J, LU W, MA C Y, et al. Effect of crack width and wet-dry cycles on the chloride penetration resistance of engineered cementitious composite (ECC)[J]. Construction and Building Materials, 2022, 352: 129030.
[28] 班顺莉. 矿物掺合料对再生混凝土界面过渡区微结构影响研究[D]. 青岛: 青岛理工大学, 2022.
BAN S L. Effect of mineral admixtures on microstructure of interface transition zone of recycled concrete[D]. Qingdao: Qingdao Tehcnology University, 2022 (in Chinese).
[29] 李瑶, 黄茗, 姜挺, 等. 基于细微观结构的再生混凝土力学性能研究[J]. 混凝土, 2022(8): 67-70.
LI Y, HUANG M, JIANG T, et al. Study on mechanical properties of recycled concrete based on microstructure[J]. Concrete, 2022(8): 67-70 (in Chinese).