落锤冲击下碳纤维增强混凝土梁的动态响应与损伤

马钢; 郭栋才; 李国强; 王卓然

doi:10.13801/j.cnki.fhclxb.20220214.002

落锤冲击下碳纤维增强混凝土梁的动态响应与损伤

doi: 10.13801/j.cnki.fhclxb.20220214.002

1.
太原理工大学　土木工程学院，太原 030024
2.
太原理工大学　机械与运载工程学院，太原 030024

基金项目: 国家自然科学基金国际合作与交流项目(5201101735)；山西省自然科学基金(201901D211108；201901D211018)

详细信息

通讯作者:
马钢，博士，副教授，硕士生导师，研究方向为混凝土结构材料　E-mail: magang@tyut.edu.cn

中图分类号: TU375.1
计量
- 文章访问数: 790
- HTML全文浏览量: 477
- PDF下载量: 60
- 被引次数: 0
出版历程
- 收稿日期: 2021-11-08
- 修回日期: 2022-01-20
- 录用日期: 2022-01-24
- 网络出版日期: 2022-02-14
- 刊出日期: 2022-11-01

Dynamic response and damage analysis of carbon fiber reinforced concrete beams under drop hammer impact

1.
College of Civil Engineering, Taiyuan University of Technology, Taiyuan 030024, China
2.
College of Mechanical and Transport Engineering, Taiyuan University of Technology, Taiyuan 030024, China

摘要

摘要: 普通混凝土在冲击载荷作用下断裂耗能能力差，而采用单丝态碳纤维掺入混凝土中制备的碳纤维增强混凝土(Carbon fiber reinforced concrete，CFRC)不仅可使混凝土衍生出多种功能性，同时可大大改善混凝土的抗冲击性能。利用落锤试验机对CFRC梁在低速冲击下的动态力学响应进行研究，在此基础上建立基于纤维随机分布的混凝土细观力学模型，研究不同纤维掺量和冲击速度对CFRC梁在低速冲击下力学响应、断裂耗能及破坏形态等的影响规律。结果表明：力学响应方面，基于随机纤维混凝土细观模型的仿真结果与试验结果符合较好；随着碳纤维体积掺量的增大，支座反力峰值变化不大，碳纤维掺量0.4vol%的混凝土梁跨中竖向位移较大，抗冲击韧性最佳。断裂耗能方面，当冲击速度低于6 m·s^–1时，增大掺量有利于碳纤维于基体中发挥桥接作用，提升CFRC梁的断裂耗能能力；随着冲击速度的增大，为保证基体非裂缝区碳纤维与混凝土之间协同耗能，进一步提高碳纤维混凝土的纤维掺量是提升冲击下CFRC耗能的关键。破坏行为方面，碳纤维掺量0.8vol%的混凝土梁在冲击下在跨中主裂缝附近呈现数量较多的斜裂纹弥散开裂行为；当冲击速度达到12 m·s^–1时，CFRC梁的破坏呈现弯剪破坏形态。本文的研究结果可为CFRC在工程中的推广应用提供参考。
- 纤维增强混凝土 /
- 落锤冲击 /
- 细观模型 /
- 动力学响应 /
- 三维细观分析
Abstract: The fracture energy dissipation capacity of ordinary concrete under impact load is poor, and the carbon fiber reinforced concrete (CFRC) prepared by adding single filament carbon fiber into concrete can not only make concrete derive a variety of functions, but also greatly improve the impact resistance of concrete. The dynamic mechanical response of CFRC beam under low velocity impact was studied by drop hammer test machine. On this basis, the meso-mechanical model of concrete based on random distribution of fiber was established, and the influences of the fiber content and impact velocity on the mechanical response, fracture energy consumption and failure mode of CFRC beam under low velocity impact were studied. The results show that in terms of mechanical response, the simulation results based on the meso-scale model of random fiber reinforced concrete are in good agreement with the experimental results. With the increase of carbon fiber volume content, the peak value of bearing reaction has little change. The mid-span vertical displacement of concrete beams with 0.4vol% carbon fiber content is larger, and the impact toughness is the best. In terms of fracture energy dissipation, when the impact velocity is lower than 6 m·s⁻¹, increasing the content of carbon fiber is beneficial to bridge the matrix and improve the fracture energy dissipation capacity of CFRC beams. With the increase of impact velocity, in order to ensure the synergistic energy consumption between carbon fiber and concrete in non-crack zone of matrix, further improving the fiber content of carbon fiber concrete is the key to improve the energy consumption of CFRC concrete under impact. In terms of failure behavior, the concrete beam with 0.8vol% carbon fiber content presents a large number of diagonal crack dispersion cracking behaviors near the main crack in the midspan under impact. When the impact velocity reaches 12 m·s⁻¹, the failure mode of CFRC beam is bending shear failure. The research results can provide reference for the application of carbon fiber reinforced concrete in engineering.
- fiber reinforced concrete /
- drop hammer impact /
- mesoscopic model /
- dynamic response /
- three-dimensional microscopic analysis

HTML全文

图 1 碳纤维增强混凝土(CFRC)梁有限元模型

RP-1, RP-2 and RP-3—Drop hammer, left bearing and right bearing, respectively

Figure 1. Finite element model of carbon fiber reinforced concrete (CFRC) beam

下载: 全尺寸图片幻灯片

图 2 碳纤维实物

Figure 2. Carbon fiber object

下载: 全尺寸图片幻灯片

图 3 水泥基试件断面碳纤维分散情况

Figure 3. Carbon fiber dispersion of cement-based specimen section

下载: 全尺寸图片幻灯片

图 4 INSTRON-9350落锤冲击试验装置

Figure 4. INSTRON-9350 drop weight impact test device

下载: 全尺寸图片幻灯片

图 5 支座反力时程曲线：(a) 预制混凝土(PC)梁；(b) CFRC梁

Figure 5. Time history curves of support reaction: (a) Precast concrete (PC) beam; (b) CFRC beam

下载: 全尺寸图片幻灯片

图 6 跨中竖向位移时程曲线：(a) PC梁；(b) CFRC梁

Figure 6. Time history curves of midspan vertical displacement: (a) PC beam; (b) CFRC beam

下载: 全尺寸图片幻灯片

图 7 冲击载荷下纤维混凝土梁的结构响应示意图

SFRC—Steel fiber-reinforced concrete

Figure 7. Structural response diagram of fiber reinforced concrete beam under impact load

下载: 全尺寸图片幻灯片

图 8 裂缝开展处碳纤维桥接作用

Figure 8. Carbon fiber bridging effect at crack development

下载: 全尺寸图片幻灯片

图 9 梁的破坏形态：(a) PC梁；(b) CFRC梁(碳纤维体积掺量0.2vol%，冲击速度3 m·s^–1)

Figure 9. Failure modes of beams: (a) PC beam; (b) CFRC beam (Carbon fiber volume content 0.2vol%, impact velocity 3 m·s^–1)

下载: 全尺寸图片幻灯片

图 10 冲击载荷下PC梁模拟破坏过程 (冲击速度3 m·s^–1)

Figure 10. Simulation of failure process of PC beam under impact load (Impact velocity 3 m·s^–1)

PE,Max.Principal—Maximum principal plastic deformation

下载: 全尺寸图片幻灯片

图 11 冲击载荷下CFRC梁模拟破坏过程(碳纤维体积掺量0.2vol%，冲击速度3 m·s^–1)

S,Max.Principal—Maximum principal stress (MPa)

Figure 11. Simulation of failure process of CFRC beam under impact load (Carbon fiber volume content 0.2vol%, impact velocity 3 m·s^–1)

下载: 全尺寸图片幻灯片

图 12 CFRC梁支座反力时程曲线

Figure 12. Time history curves of support reaction force of CFRC beam

下载: 全尺寸图片幻灯片

图 13 CFRC梁跨中竖向位移时程曲线

Figure 13. Time history curves of midspan vertical displacement of CFRC beam

下载: 全尺寸图片幻灯片

图 14 CFRC梁支座反力-位移曲线

Figure 14. Support reaction-displacement curves of CFRC beam

下载: 全尺寸图片幻灯片

图 15 不同碳纤维体积掺量CFRC试件断裂耗能

Figure 15. Fracture energy dissipation of CFRC specimens with different volume fractions of carbon fiber

下载: 全尺寸图片幻灯片

图 16 不同碳纤维体积掺量的CFRC梁破坏形态(冲击速度3 m·s^–1)

Figure 16. Failure modes of CFRC beams with different volume fractions of carbon fiber (Impact velocity 3 m·s^–1)

下载: 全尺寸图片幻灯片

图 17 不同碳纤维体积掺量的CFRC梁破坏形态(冲击速度12 m·s^–1)

Figure 17. Failure modes of CFRC beams with different volume fractions of carbon fiber (Impact velocity 12 m·s^–1)

下载: 全尺寸图片幻灯片

图 18 CFRC梁支座反力时程曲线

Figure 18. Time history curves of support reaction force of CFRC beams

下载: 全尺寸图片幻灯片

图 19 CFRC梁跨中竖向位移时程曲线

Figure 19. Time history curves of midspan vertical displacement of CFRC beams

下载: 全尺寸图片幻灯片

图 20 CFRC梁支座反力-位移曲线

Figure 20. Support reaction-displacement curves of CFRC beams

下载: 全尺寸图片幻灯片

图 21 不同冲击速度下CFRC梁试件断裂耗能

Figure 21. Fracture energy dissipation of CFRC beam specimens under different impact velocities

下载: 全尺寸图片幻灯片

图 22 不同冲击速度下CFRC梁破坏形态

Figure 22. Failure modes of CFRC beams under different impact velocities

下载: 全尺寸图片幻灯片

图 23 不同冲击速度下CFRC梁破坏形态

Figure 23. Failure modes of CFRC beams under different impact velocities

下载: 全尺寸图片幻灯片

表 1 混凝土模型参数

Table 1. Parameters of concrete model

Parameter	Dilation angle/(°)	Flow potential offset/mm	Ultimate strength ratio of biaxial compression to uniaxial compression	Invariable stress ratio	Coefficient of viscosity/ (Ns·m⁻²）	Density/ (kg·m⁻³)	Young's modulus/ GPa	Poisson ratio
Value	38	0.1	1.16	0.667	0.00001	2400	32.5	0.2

下载: 导出CSV

表 2 纤维物理力学性能

Table 2. Physical and mechanical properties of fiber

Fiber type	Density/(g·cm⁻³)	Tensile strength/MPa	Elastic modulus/GPa	Percentage elongation/%
Carbon fiber	1.78	3530	230	1.5

下载: 导出CSV

表 3 混凝土配合比

Table 3. Proportioning of concrete kg·m⁻³

	Water	Cement	Coarse aggregate	Fine aggregate	Dispersing agent	Water reducer	Defoaming agent
	220	400	1200	680	0.8	0.8	0.12

下载: 导出CSV

表 4 CFRC试件编号

Table 4. CFRC test number

Number	Drop hammer quality/kg	Volume content of CF/vol%	Impact velocity/(m·s⁻¹)
0.0vol%CF/C-3	20.52	0.0	3
0.2vol%CF/C-3	20.52	0.2	3
0.4vol%CF/C-3	20.52	0.4	3
0.8vol%CF/C-3	20.52	0.8	3
0.0vol%CF/C-12	20.52	0.0	12
0.2vol%CF/C-12	20.52	0.2	12
0.4vol%CF/C-12	20.52	0.4	12
0.8vol%CF/C-12	20.52	0.8	12
Notes: CF—Carbon fiber; C—Concrete.

下载: 导出CSV

表 5 不同碳纤维体积掺量的CFRC梁模拟结果

Table 5. Simulation results of CFRC beams with different volume fraction of carbon fiber

Number	Peak value of impact force/kN	Maximum vertical displacement/mm
0.0vol%CF/C-3	28.36	2.15
0.2vol%CF/C-3	28.11	2.61
0.4vol%CF/C-3	30.37	2.85
0.8vol%CF/C-3	31.21	2.86
0.0vol%CF/C-12	29.03	2.31
0.2vol%CF/C-12	28.44	3.31
0.4vol%CF/C-12	27.94	3.71
0.8vol%CF/C-12	25.69	4.25

下载: 导出CSV

表 6 不同冲击速度下CFRC梁模拟结果

Table 6. Simulation results of CFRC beams under different impact velocities

Number	Drop hammer quality/kg	Peak value of impact force/kN	Maximum vertical displacement/mm
0.4vol%CF/C-1.5	20.52	34.19	1.36
0.4vol%CF/C-3	20.52	30.37	2.85
0.4vol%CF/C-6	20.52	29.67	3.58
0.4vol%CF/C-12	20.52	27.94	3.71
0.8vol%CF/C-1.5	20.52	36.45	1.00
0.8vol%CF/C-3	20.52	31.21	2.86
0.8vol%CF/C-6	20.52	27.42	3.60
0.8vol%CF/C-12	20.52	25.69	4.25

下载: 导出CSV

参考文献(29)

[1]	SOHEL K M A, AI-JABRI K, AI ABRI A H S. Behavior and design of reinforced concrete building columns subjected to low-velocity car impact structures[J]. Elsevier,2020,26:601-616.
[2]	周晓宇, 马如进, 陈艾荣. 行车落物冲击下钢筋混凝土桥面板的安全性能[J]. 华南理工大学学报(自然科学版), 2018, 46(4):137-145. ZHOU Xiaoyu, MA Rujin, CHEN Airong. Safety perfor-mance of a bridge deck under impact of a massive falling cargo from passing truck[J]. Journal of South China University of Technology (Natural Science Edition),2018,46(4):137-145(in Chinese).
[3]	LIU S M, CUI K P, HE X, et al. Dynamic simulation analysis based on LS-DYNA about impact force on bridge pier caused by vehicle[J]. Railway Standard Design,2013(8):70-74.
[4]	BIBORA P, DRDLOVA M, PRACHAR V, et al. The impact of various types of steel fibres on the strength parameters and blast resistance of high performance concrete[J]. Materials Science and Engineering,2019,596:1-10.
[5]	YOO D Y, BANTHIA N. Impact resistance of fiber-reinforced concrete: A review[J]. Cement and Concrete Composites,2019,104:103389. doi: 10.1016/j.cemconcomp.2019.103389
[6]	刘玲玲. 碳纤维织物增强混凝土薄板力学性能研究[D]. 长沙: 湖南大学, 2017. LIU Lingling. Research on the mechanical properties of carbon textile reinforced concrete thin plates[D]. Changsha: Hunan University, 2017(in Chinese).
[7]	程小全, 康炘蒙, 邹健, 等. 平面编织复合材料层合板低速冲击后的拉伸性能[J]. 复合材料学报, 2008, 25(5):163-168. doi: 10.3321/j.issn:1000-3851.2008.05.027 CHENG Xiaoquan, KANG Xinmeng, ZOU Jian, et al. Tensile properties of plane woven composite laminates after low velocity impact[J]. Acta Materiae Compositae Sinica,2008,25(5):163-168(in Chinese). doi: 10.3321/j.issn:1000-3851.2008.05.027
[8]	TSESARSKY M, PELED A, KATZ A, et al. Strengthening concrete elements by confinement within textile reinforced concrete (TRC) shells static and impact properties[J]. Construction and Building Materials,2013,44:514-523. doi: 10.1016/j.conbuildmat.2013.03.031
[9]	ZHU M, ZHU J H, UEDA T, et al. Bond behavior of carbon fabric reinforced cementitious matrix (FRCM) composites considering matrix impregnation[J]. Composite Structures,2021,262:113350. doi: 10.1016/j.compstruct.2020.113350
[10]	ZAKI M A, RASHEED H A. Characterizing debonding strain in sand-lightweight high strength concrete T beams strengthened with CFRP sheets[J]. Composite Structures,2021,262:113630. doi: 10.1016/j.compstruct.2021.113630
[11]	WEI A, AL-AMERI R, KOAY Y C, et al. Triple-functional carbon fibre reinforced polymer for strengthening and protecting reinforced concrete structures[J]. Composites Communications,2021,24:100648. doi: 10.1016/j.coco.2021.100648
[12]	LI P, YANG T, ZENG Q, et al. Axial stress-strain behavior of carbon FRP-confined seawater sea-sand recycled aggre-gate concrete square columns with different corner radii[J]. Composite Structures,2021,262:113589. doi: 10.1016/j.compstruct.2021.113589
[13]	SHAH S P. Concrete and fiber reinforced concrete subjected to impact loading[J]. MRS Online Proceedings Library,1985,64(1):181-201.
[14]	LAVAGNA L, MUSSO S, FERRO G, et al. Cement-based composites containing functionalized carbon fibers[J]. Cement and Concrete Composites,2018,88:165-171. doi: 10.1016/j.cemconcomp.2018.02.007
[15]	WANG C, JIAO G S, LI B L, et al. Dispersion of carbon fibers and conductivity of carbon fiber-reinforced cement-based composites[J]. Ceramics International,2017,43(17):15122-15132. doi: 10.1016/j.ceramint.2017.08.041
[16]	CHUNG D D L. Cement reinforced with short carbon fibers: A multifunctional material[J]. Composites Part B: Engineering,2000,31(6-7):511-526. doi: 10.1016/S1359-8368(99)00071-2
[17]	张剑, 王立峰, 叶见曙. 碳纤维增强复合材料筋混凝土梁非线性力学性能[J]. 复合材料学报, 2009, 26(4):156-162. doi: 10.3321/j.issn:1000-3851.2009.04.028 ZHANG Jian, WANG Lifeng, YE Jianshu. Nonlinear mecha-nical properties of concrete beam with carbon fiber reinforced composite rebars[J]. Acta Materiae Compositae Sinica,2009,26(4):156-162(in Chinese). doi: 10.3321/j.issn:1000-3851.2009.04.028
[18]	ZAHRA S T, JEFFERY S, DARWIN I, et al. Experimental and numerical analysis of long carbon fiber reinforced concrete panels exposed to blast loading[J]. International Journal of Impact Engineering,2013,57:70-80. doi: 10.1016/j.ijimpeng.2013.01.006
[19]	GAO N, LI B L, ZHAO L P, et al. Influences of molding processes and different dispersants on the dispersion of chopped carbon fibers in cement matrix[J]. Heliyon,2018,4(10):e00868. doi: 10.1016/j.heliyon.2018.e00868
[20]	HAMBACH M, MOLLER H, NEUMANN T, et al. Portland cement paste with aligned carbon fibers exhibiting exceptionally high flexural strength (>100 MPa)[J]. Cement and Concrete Research,2016,89:80-86. doi: 10.1016/j.cemconres.2016.08.011
[21]	TABATABAEI Z S, VOLZ J S, KEENER D I, et al. Compara-tive impact behavior of four long carbon fiber reinforced concretes[J]. Materials & Design,2014,55:212-223.
[22]	GAO J, LIU Z Z, SHA A, et al. Characterization of carbon fiber distribution in cement-based composites by computed tomography[J]. Construction and Building Materials,2018,177:134-147. doi: 10.1016/j.conbuildmat.2018.05.114
[23]	XU Z, HAO H, LI H N. Mesoscale modelling of fibre reinforced concrete material under compressive impact loading[J]. Construction and Building Materials,2012,26(1):274-288. doi: 10.1016/j.conbuildmat.2011.06.022
[24]	CHIARELLO M, ZINNO R. Electrical conductivity of self-monitoring CFRC[J]. Cement and Concrete Composites,2005,27(4):463-469. doi: 10.1016/j.cemconcomp.2004.09.001
[25]	HAFNER S, ECKARDT S, LUTHER T, et al. Mesoscale modeling of concrete: Geometry and numerics[J]. Computers & Structures,2006,84(7):450-461.
[26]	赵燕茹, 郝松, 王磊, 等. 基于数字图像相关的钢纤维增强水泥基复合材料的冲击损伤特性[J]. 复合材料学报, 2018, 35(5):1325-1331. ZHAO Yanru, HAO Song, WANG Lei, et al. Impact damage characteristics of steel fiber reinforced cement matrix composites based on digital image correlation[J]. Acta Materiae Compositae Sinica,2018,35(5):1325-1331(in Chinese).
[27]	FANG Q, ZHANG J H. Three-dimensional modelling of steel fiber reinforced concrete material under intense dynamic loading[J]. Construction and Building Materials,2013,44:118-132. doi: 10.1016/j.conbuildmat.2013.02.067
[28]	LIANG X W, WU C Q. Meso-scale modelling of steel fibre reinforced concrete with high strength[J]. Construction and Building Materials,2018,165:187-198. doi: 10.1016/j.conbuildmat.2018.01.028
[29]	中国建筑科学研究院. 混凝土结构设计规范: GB/T 50010—2010[S]. 北京: 中国建筑工业出版社, 2010. China Academy of Building Sciences. Code for design of concrete structures: GB/T 50010—2010[S]. Beijing: China Construction Industry Press, 2010(in Chinese).