短切碳纤维增强混凝土动态抗拉性能研究

doi:10.19936/j.cnki.2096-8000.20220928.014

摘要/Abstract

摘要： 由于混凝土抗拉、抗压强度的不均匀性,在混凝土中添加碳纤维可以改善混凝土的静态抗拉性能,提高拉压比。考虑到冲击和爆炸荷载对混凝土的破坏,本文研究了应力速率和碳纤维含量对混凝土动态抗拉性能的影响,并从细观层次上探讨其抗拉强度在动、静态性能上的差异。采用直径为74 mm的分离式霍普金森压杆(SHPB)装置,对含纤维体积分数分别为0‰、1‰、2‰和3‰的混凝土进行了动态劈裂试验。结果表明,随着纤维含量的增加,混凝土的静态抗拉强度明显增加,但增加的幅度有减小趋势。动态抗拉强度和动态强度增加因子(DIF)均随应力速率的增加而增加,表现出明显的率效应。碳纤维对混凝土动、静强度的影响存在显著差异。在设计混凝土配合比时,应适当选择碳纤维含量,以满足具体工况动、静态力学性能的要求。

关键词: 碳纤维, SHPB, 抗拉性能, DIF, 细观, 混凝土

Abstract: Due to the non-uniform tension and compression strength of concrete, carbon fiber can be added to concrete to improve its static tensile behavior and increase the tension-compression ratio. In view of the destructive consequences of impacts and explosions, the effects of the stress rates and carbon fiber contents on the dynamic tension behavior of concrete were investigated in this paper. And from the mesoscopic level, the difference between the dynamic and static properties of its tensile strength is discussed. The dynamic splitting tests of concrete with the fiber contents of 0‰, 1‰, 2‰, and 3‰ were carried out by using a split Hopkinson pressure bar (SHPB) device with a diameter of 74 mm. We found that with the increase of fiber content, the static tensile strength of concrete increases obviously, but the increased amplitude tends to decrease. The dynamic tensile strength and dynamic increase factor (DIF) both increase with the increase of stress rate, but the growth rate slows down, showing an obvious rate effect. There are significant differences in the influence of carbon fiber on the dynamic and static strength of concrete. In the design of concrete mixing proportion, the content of carbon fiber should be appropriately selected to meet the requirements of dynamic and static mechanical properties.

Key words: carbon fiber, SHPB, tensile strength, DIF, mesoscopic, concrete

中图分类号:

TB332

刘玉娟, 王丽娟. 短切碳纤维增强混凝土动态抗拉性能研究[J]. 复合材料科学与工程, 2022, 0(9): 97-101.

LIU Yu-juan, WANG Li-juan. Study on dynamic tensile properties of short-cut carbon fiber reinforced concrete[J]. COMPOSITES SCIENCE AND ENGINEERING, 2022, 0(9): 97-101.

参考文献

[1] 李杰, 卢朝辉, 张其云. 混凝土随机损伤本构关系—单轴受压分析[J]. 同济大学学报, 2003, 31(5): 505-509.
[2] 石晓宇, 王巍. 轻骨料混杂纤维喷射混凝土静动态力学性能试验研究[J]. 混凝土, 2021(8): 24-29.
[3] PAKRAVAN H R, LATIFI M, JAMSHIDI M. Hybrid short fiber reinforcement system in concrete: A review[J]. Construction and Building Materials, 2017(142): 280-294.
[4] 张培辉, 方圣恩, 洪华山. 不同纤维增强混凝土力学性能和破坏形态对比试验[J]. 玻璃钢/复合材料, 2019(6): 73-79.
[5] 王晨飞, 焦俊婷. 超细钢-聚丙烯混杂纤维混凝土力学性能研究[J]. 玻璃钢/复合材料, 2016(12): 11-14.
[6] LI X J, ZHANG Y Y, SHI C, et al. Experimental and numerical study on tensile strength and failure pattern of high performance steel fiber reinforced concrete under dynamic splitting tension[J]. Construction and Building Materials, 2020, 259: 119796.
[7] 李曈, 张晓东, 范锦泽, 等. 高吸水树脂玄武岩纤维混凝土力学性能试验研究[J]. 玻璃钢/复合材料, 2019(12): 29-33.
[8] 侯敏, 陶燕, 陶忠, 等. 短切碳纤维混凝土的基本力学性能与分析[J]. 混凝土, 2020(1): 74-77.
[9] WEN S H, CHUNG D D L. Enhancing the Seebeck effect in carbon fiber-reinforced cement by using intercalated carbon fibers[J]. Cement and Concrete Research, 2000(30): 1295-1298.
[10] CHUNG D D L. Carbon fiber reinforced cement mortar improved by using acrylic dispersion as admixture[J]. Cement and Concrete Research, 2001(31): 1633-1637.
[11] MASTALI M, DALVAND A, SATTARIFARD A. The impact resistance and mechanical properties of the reinforced self-compacting concrete incorporating recycled CFRP fiber with different lengths and dosages[J]. Composites Part B-Engineering, 2017(112): 74-92.
[12] XIONG B, WANG Z, WANG C, et al. Effects of short carbon fiber content on microstructure and mechanical property of short carbon fiber reinforced Nb/Nb5Si3 composites[J]. Intermetallics, 2019(106): 59-64.
[13] 周乐, 王晓初, 刘洪涛. 碳纤维混凝土应力-应变曲线试验研究[J]. 工程力学, 2013, 30(7): 200-204.
[14] 刘文勇, 袁璞, 马冬冬, 等. 短切碳纤维混凝土单轴冲击压缩试验与分析[J]. 混凝土与水泥制品, 2004(5): 46-49.
[15] LU Y, LI Q. About the dynamic uniaxial tensile strength of concrete-like materials[J]. International Journal of Impact Engineering, 2011, 36(4): 171-180.
[16] CUSATIS G. Strain-rate effects on concrete behaviour[J]. International Journal of Impact Engineering, 2011(38): 162-170.
[17] GUO Z, ZHUANG C L, LI Z H, et al. Mechanical properties of carbon fiber reinforced concrete (CFRC) after exposure to high temperatures[J]. Composite Structures, 2021, 256: 113072.
[18] LI X F, LI X, LI H B, et al. Dynamic tensile behaviours of heterogeneous rocks: The grain scale fracturing characteristics on strength and fragmentation[J]. International Journal of Impact Engineering, 2018(118): 98-118.
[19] 李夕兵. 岩石动力学基础与应用[M]. 北京: 科学出版社, 2014.
[20] 龙广成, 李宁, 薛逸骅, 等. 冲击荷载作用下掺橡胶颗粒自密实混凝土的力学性能[J]. 硅酸盐学报, 2016, 44(8): 1081-1090.
[21] GURUSIDESWAR S, SHUKLA A, JONNALAGADDA K N, et al. Tensile strength and failure of ultra-high performance concrete (UHPC) composition over a wide range of strain rates[J]. Construction and Building Materials, 2020(114): 258.
[22] TRAN T K, KIM D J. Investigating direct behaviour of high performance fibre reinforced cementitious composites at high strain rates[J]. Cement and Concrete Research, 2013(50): 62-73.