为研究不同掺量的植物纤维(plant fiber,PF)对植物纤维喷射混凝土(plant fiber shotcrete,PFSC)基本力学性能及导热系数的影响规律,借助扫描电镜(scanning electron microscope,SEM)试验对PFSC的微观结构进行分析。结果表明:相较于素喷射混凝土,掺量为2.0 kg/m3的PFSC抗压强度和劈裂抗拉强度分别提高了17.35%和20.26%,导热系数降低了20.61%。SEM分析表明,低掺量PF在喷射混凝土内部具有较好的分散性,与混凝土基体界面粘结性较好,但PF掺量过高时会出现纤维结团现象,使得PFSC内部缺陷增加。综合力学性能试验结果,建议混凝土PF掺量不宜>2.0 kg/m3。研究成果对于植物纤维喷射混凝土的推广应用有一定参考价值。
Abstract
The microstructure of plant fiber shotcrete (PFSC) is analyzed by means of scanning electron microscopy (SEM) in a purpose of investigating the influence of plant fiber dosage on the mechanical properties and thermal conductivity of PFSC. Compared with those of plain shotcrete, the compressive strength and splitting tensile strength of PFSC dosed with 2.0 kg/m3 plant fiber increase by 17.35% and 20.26%, respectively, while the thermal conductivity reduces by 20.61%. SEM analysis shows that plant fiber in low-volume well disperses in the interior of the shotcrete and adheres to the concrete matrix. However, large content of plant fiber agglomerates in the shotcrete, leading to more internal defects of PFSC. According to the comprehensive mechanical properties test results, we recommend that the plant fiber content should not exceed 2.0 kg/m3.
关键词
喷射混凝土 /
植物纤维 /
力学性能 /
导热系数 /
微观性能
Key words
shotcrete /
plant fiber /
mechanical properties /
thermal conductivity /
microscopic performance
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 王家滨,牛荻涛. 喷射混凝土力学性能试验研究及预测模型建立[J]. 硅酸盐通报,2019,38(1):125-131.
[2] HOOSHECHIN M, TANZADE J. Experimental and Mechanical Performance of Shotcrete Made with Nanomaterials and Fiber Reinforcement[J]. Construction and Building Materials, 2018, 165: 199-205.
[3] BERNARD E S. Age-dependent Changes in Post-crack Performance of Fibre Reinforced Shotcrete Linings[J]. Tunnelling and Underground Space Technology, 2015, 49: 241-248.
[4] 宋梓宁,周林聪. 秸秆混凝土的导热系数及抗压承载力的试验研究[J]. 水利与建筑工程学报,2015,13(1):148-150,166.
[5] 张 强,李耀庄,刘保华. 秸秆资源在混凝土中应用的研究进展[J]. 硅酸盐通报,2015,34(4):1000-1003.
[6] 李超飞,苏有文,陈国平. 植物纤维混凝土的研究现状[J]. 混凝土,2013(5):55-56,61.
[7] 胡玉龙,陈国新,陈亮亮. 植物纤维增强型玻化微珠陶粒混凝土配合比设计[J]. 混凝土与水泥制品,2015(1):65-68.
[8] IZQUIERDO I S, RAMALHO M, IZQUIERDO O S. Post-cracking Behavior of Blocks, Prisms, and Small Concrete Walls Reinforced with Plant Fiber[J]. Revista IBRACON de Estruturas et Materiais, doi: 10.1590/S1983-41952013000400006.
[9] FERREIRA C R, TAVARES S, FERREIRA B H M, et al. Comparative Study about Mechanical Properties of Structural Standard Concrete and Concrete with Addition of Vegetable Fibers[J]. Materials Research,2017,20(2):102-107.
[10]ABBAS N, KHALID H R, BAN G, et al. Silica Aerogel Derived from Rice Husk: An Aggregate Replacer for Lightweight and Thermally Insulating Cement-based Composites[J]. Construction and Building Materials, 2018,195:312-322.
[11]赵树琪,李 蔚,戴宝生,等.棉花秸秆综合利用现状分析[J].湖北农业科学,2017,56(12):2201-2203.
[12]LIU Chao, XU Gui-zhong, XU Bing. Field Study on the Vacuum Preloading of Dredged Slurry with Wheat Straw Drainage[J]. KSCE Journal of Civil Engineering, 2018,22(11): 4327-4333.
[13]JGJ/T 372—2016,喷射混凝土应用技术规程[S].北京:中国建筑工业出版社,2016.
[14]GB/T 50081—2002,普通混凝土力学性能试验方法标准[S]. 北京:中国建筑工业出版社,2002.
[15]GB/T 10294—2008,绝热材料稳态热阻及有关特性的测定防护热板法[S]. 北京:中国标准出版社,2008.
[16]焦华喆,韩振宇,陈新明,等. 玄武岩纤维对喷射混凝土力学性能及微观结构影响机制[J]. 复合材料学报2019,36(8):1-9.
[17]郭平业,秦 飞. 张双楼煤矿深井热害控制及其资源化利用技术应用[J]. 煤炭学报,2013,38(增刊2):393-398.
[18]何满潮,郭平业,陈学谦,等. 三河尖矿深井高温体特征及其热害控制方法[J]. 岩石力学与工程学报,2010,29(增刊1):2593-2597.
[19]庞建勇,黄金坤,姚文杰,等.巷道隔热喷射混凝土强度及导热性能试验研究[J].raybet体育在线
院报,2018,35(2):119-124.
基金
安徽省高校自然科学重大项目(KJ2015ZD20);淮南市科技计划重大创新平台及创新人才团队专项(2017A055)
PDF(4677 KB)
