Experimental study on the pre-tightened tooth connection of carbon fiber reinforced polymer
-
摘要: 为探明桥梁用碳纤维增强树脂复合材料(CFRP)预紧力齿连接破坏模式和承载性能,以预紧力(23 MPa、34.6 MPa、53 MPa、64.5 MPa)、齿深(0.5 mm、1 mm、2 mm)、齿长(8 mm、16 mm、24 mm)和齿数(1道齿、3道齿和6道齿)为变化参数, 进行了共计68个预紧力齿连接接头拉伸试验。根据荷载-位移曲线、应变及破坏模式的测试结果,分析了各参数变化对复合材料预紧力齿连接接头力学性能的影响。研究结果表明:CFRP预紧力齿连接接头存在4种破坏模式−剪切破坏、压溃破坏、纵向劈裂和纤维拉断;接头荷载-位移曲线有两种特征,荷载在达到极值后突然下降及荷载在达到极值后缓慢下降,前者接头发生剪切或纤维拉断破坏,后者接头发生压溃或劈裂破坏;预紧力多齿接头荷载分配不均匀,发生压溃破坏的接头比发生剪切破坏的接头内力分配更均匀,不管接头发生压溃破坏还是剪切破坏,第一道齿承担的载荷分配比最大,齿数越多,接头的最大载荷分配比越小,当预紧力超过53 MPa时,预紧力变化对接头破坏时第一道齿的影响不明显;当预紧力、齿深和齿长分别小于53 MPa、2 mm和16 mm时,接头连接强度分别随预紧力、齿深和齿长的增加而增加,当预紧力和齿长分别超过53 MPa和16 mm时,接头连接强度变化不大,在6齿范围内,接头连接强度随齿数的增加而增加。
-
关键词:
- 桥梁工程 /
- 预紧力齿连接 /
- 试验 /
- 承载性能 /
- 碳纤维增强树脂复合材料
Abstract: To investigate the failure modes and load-bearing performance of pre-tightened tooth connections of carbon fiber reinforced polymer (CFRP) in the bridge engineering, a total of 68 tensile specimens were carried out with transverse pre-tightened force (23 MPa, 34.6 MPa, 53 MPa, 64.5 MPa), tooth depth (0.5 mm, 1 mm, 2 mm), tooth length (8 mm, 16 mm, 24 mm) and tooth number (one tooth, three teeth and six teeth) as variable parameters. According to the test results of load displacement curve, strain and failure mode, the effects of various parameters on the mechanical properties of the joint were analyzed. The results show that there are four failure modes for CFRP pre-tightened tooth joints: Shear failure, crushing failure, longitudinal splitting failure and fiber breaking failure. There are two characteristics of the load-displacement curves of the joint: The load drops suddenly after reaching the extreme value and the load decreases slowly after reaching the extreme value. The former joints are subjected to shear failure or fiber breaking failure, while the latter joint is subjected to crushing failure or splitting failure. The load distribution ratio of pre-tightened multi-tooth joints is uneven, the load distribution ratio of the joint with crushing failure is more uniform than that of joint with shear failure. Whether the joint is crushing or shear failure, the load distribution ratio of the first tooth is the largest. The more the number of joint teeth, the smaller the maximum load distribution ratio of the joint. When the pre-tightened force, tooth depth and tooth length are less than 53 MPa, 2 mm and 16 mm respectively, the joint strength increases with the increase of pre-tightened force, tooth depth and tooth length. When the pre-tightened force and tooth length exceed a certain value of 53 MPa and 16mm respectively, the joint connection strength changes little. In the range of 6 teeth, the joint strength increases with the increase of the number of teeth. -
表 1 碳纤维增强树脂复合材料(CFRP)板力学参数
Table 1. Mechanical parameters of carbon fiber reinforced polymer (CFRP) plate
$ {E_a} $/GPa $ {E_b} $/GPa $ {E_c} $/GPa $ {G_{ab}} $/GPa $ {\upsilon _{ab}} $ $ {X_{\text{t}}} $/MPa $ {X_{\text{c}}} $/MPa $ {Y_{\text{t}}} $/MPa $ {Y_{\text{c}}} $/MPa $ S_{ab}^{} $/MPa 108.9 8.8 8.8 3 0.33 1480 613.4 65 205 54 Notes: a—Fiber direction, whereas b and c are perpendicular to a. For example, ${G_{ab}}$—Shear modulus in the plane a–b; ${S_{ab}}$—Shear strength in the plane a–b; ${X_{\text{t}}}$ and ${X_{\text{c}}}$—Tensile and compressive strengths, respectively, along the fiber direction; ${Y_{\text{t}}}$ and ${Y_{\text{c}}}$—Tensile and compressive strengths perpendicular to the fiber direction; Ea, Eb, Ec—Elastic modulus in a, b and c directions, respectively; νab—Poisson's ratio in the plane a–b. 表 2 Q345钢板力学参数
Table 2. Mechanical parameters of Q345 plate
Material Young’s modulus/GPa Yield strength/MPa Poisson’s ratio Q345 210 345 0.3 表 3 CFRP预紧力齿连接试件分组
Table 3. Grouping of CFRP pre-tightened tooth specimens
Material type Group Serial number Tooth
depth/mmTooth
length/mmPre-tightened
force/MPaTorque of
single bolt/(N·m)Number of
specimensCFRP A 6T-16-2-23 2 16 23 10 6 6T-16-2-34.6 34.6 15 6T-16-2-53 53 23 6T-16-2-64.5 64.5 28 B 1T-8-0.5-53 0.5 8 53 11.1 1 3T-8-0.5-53 13.5 3 6T-8-0.5-53 14.6 6 C 1T-8-1-53 1 11.1 1 3T-8-1-53 13.5 3 6T-8-1-53 14.6 6 D 1T-8-2-53 2 11.1 1 3T-8-2-53 13.5 3 6T-8-2-53 14.6 6 E 1T-16-0.5-53 0.5 16 53 16 1 3T-16-0.5-53 20.9 3 6T-16-0.5-53 23 6 F 1T-16-1-53 1 16 1 3T-16-1-53 20.9 3 6T-16-1-53 23 6 G 1T-16-2-53 2 16 1 2T-16-2-53 19.3 2 3T-16-2-53 20.9 3 4T-16-2-53 21.9 4 5T-16-2-53 22.5 5 6T-16-2-53 23 6 H 1T-24-0.5-53 0.5 24 53 20.9 1 3T-24-0.5-53 28.3 3 6T-24-0.5-53 31.4 6 I 1T-24-1-53 1 20.9 1 3T-24-1-53 28.3 3 6T-24-1-53 31.4 6 J 1T-24-2-53 2 20.9 1 3T-24-2-53 28.3 3 6T-24-2-53 31.4 6 Notes: Serial number nT-L-H-P, where n—Number of teeth; L—Tooth length; H—Tooth depth; P—Preloading force. 表 4 CFRP复合材料预紧力齿连接接头破坏时各个齿的荷载分配比
Table 4. Load distribution ratio of each tooth when CFRP pre-tightened tooth connection failure
Serial
numberTooth
numberFailure
modesLoad distribution ratio 1# 2# 3# 4# 5# 6# 3T-16-0.5-53 3 Crushing 0.367 0.328 0.305 — — — 3T-16-2-53 3 Shear 0.426 0.232 0.342 — — — 6T-16-2-53 6 Shear 0.201 0.198 0.191 0.170 0.138 0.102 6T-16-2-64.5 6 Shear 0.198 0.120 0.196 0.172 0.171 0.143 表 5 CFRP复合材料预紧力齿连接接头承载力
Table 5. Bearing capacities of CFRP pre-tightened tooth connection
Group Serial number Bearing capacity
P/kNAverage value of
bearing capacity Pu/kNConnection
strength σ/MPaFailure mode A 6T-16-2-23 112.48/130.53 121.51 549.82 Shear 6T-16-2-34.6 157.6/153.21 155.41 703.21 Shear 6T-16-2-53 171.6/180.54 176.07 796.70 Shear 6T-16-2-64.5 174/177.15 175.58 794.48 Shear B 1T-8-0.5-53 18.1/19 18.55 83.94 Shear 3T-8-0.5-53 41.57/45.72 43.65 197.51 Shear 6T-8-0.5-53 78.72/103.31 91.02 411.86 Shear C 1T-8-1-53 19.86/20 19.93 90.18 Shear 3T-8-1-53 53.47/55 54.24 245.43 Shear 6T-8-1-53 82.14/102.4 92.27 417.51 Shear D 1T-8-2-53 26.49/24 25.25 114.25 Shear 3T-8-2-53 52.52/60.96 56.74 256.74 Shear 6T-8-2-53 131.55/130 130.78 591.76 Shear E 1T-16-0.5-53 25.99/27.57 26.78 121.18 Crushing 3T-16-0.5-53 79.11/77.82 78.47 355.07 Crushing, spitting 6T-16-0.5-53 154.36/166.33 160.35 725.57 Crushing, spitting F 1T-16-1-53 34.9/37.05 35.98 162.81 Shear 3T-16-1-53 98.8/106.18 102.5 463.80 Shear 6T-16-1-53 172/205.8 188.9 854.75 Shear, fiber broken G 1T-16-2-53 43.3/43.95 43.63 197.42 Shear 2T-16-2-53 79.62/82.44 81.03 366.65 Shear 3T-16-2-53 99.3/114.08 106.69 482.76 Shear 4T-16-2-53 140/138.86 139.43 630.90 Shear 5T-16-2-53 157.85/170.66 164.26 743.26 Shear 6T-16-2-53 171.6/180.54 176.07 796.70 Shear H 1T-24-0.5-53 38.15/39 38.58 174.57 Crushing, spitting 3T-24-0.5-53 97.85/98 97.93 443.12 Crushing, spitting 6T-24-0.5-53 158.65/173.3 165.98 751.04 Crushing, fiber broken I 1T-24-1-53 41.65/42.9 42.28 191.31 Crushing 3T-24-1-53 127.98/125 126.49 572.35 Crushing 6T-24-1-53 186.58/192.06 189.32 856.65 Crushing, fiber broken J 1T-24-2-53 42.53/44 43.27 195.79 Shear 3T-24-2-53 115.25/86 100.62 455.29 Shear 6T-24-2-53 191/205.16 198.08 896.29 Shear -
[1] 叶列平, 冯鹏. FRP在工程结构中的应用与发展[J]. 土木工程学报, 2006(3):24-36. doi: 10.3321/j.issn:1000-131X.2006.03.004YE Lieping, FENG Peng. Applications and development of fiber-reinforced polymer in engineering structures[J]. China Civil Engineering Journal,2006(3):24-36(in Chinese). doi: 10.3321/j.issn:1000-131X.2006.03.004 [2] WANG X, PENG Z Q, WU Z S, et al. High-performance composite bridge deck with prestressed basalt fiber-reinforced polymer shell and concrete[J]. Engineering Structures,2019,201:109852. doi: 10.1016/j.engstruct.2019.109852 [3] 刘路路, 汪昕, 吴智深. 基于构件-节点一体化设计纤维增强复合材料桁架结构节点性能研究[J]. 工业建筑, 2019, 49(9):109-112, 172.LIU Lulu, WANG Xin, WU Zhishen, et al. Research on connection performance of FRP truss structure based on integrated performance of member and connection[J]. Industrial Construction,2019,49(9):109-112, 172(in Chinese). [4] 徐以扬, 方海, 刘伟庆. 复合材料拉挤型材在桁架桥梁结构中的应用与发展[J]. 世界桥梁, 2010(4):32-34, 38.XU Yiyang, FANG Hai, LIU Weiqing. Application and de-velopment of composite pultruded profiles in truss bridge structures[J]. World Bridges,2010(4):32-34, 38(in Chinese). [5] 白玉磊, 梅世杰, 张玉峰, 等. 基于刚度的大应变 FRP 约束混凝土模型及其在桥梁抗震加固中的应用[J]. 中国公路学报, 2022, 35(2):115-123. doi: 10.3969/j.issn.1001-7372.2021.01.001BAI Yulei, MEI Shijie, ZHANG Yufeng, et al. Stiffness-based design-oriented model for large-rupture-strain (LRS) FRP-confined concrete and its application in seismic analysis of bridge retrofitting[J]. China Journal of Highway and Transport,2022,35(2):115-123(in Chinese). doi: 10.3969/j.issn.1001-7372.2021.01.001 [6] 滕锦光. 新材料组合结构[J]. 土木工程学报, 2018, 51(12):1-11.TENG Jinguang. New-material hybrid structures[J]. China Civil Engineering Journal,2018,51(12):1-11(in Chinese). [7] TEIXEIRA A, PFEIL M S, BATTISTA R C. Structural evaluation of a GFRP truss girder for a deployable bridge[J]. Composite Structures,2014,110(4):29-38. [8] SEDLACEK G, TRUMPF H, CASTRISCHER U. Development of a light-weight emergency bridge[J]. Structural Engineering International,2004,14(4):282-287. doi: 10.2749/101686604777963702 [9] KOSTOPOULOS V, MARKOPOULOS Y P, VLACHOS D E, et al. Design and construction of a vehicular bridge made of glass/polyester pultruded box beams[J]. Plastics Rubber and Composites,2005,34(4):201-207. doi: 10.1179/174328905X55641 [10] 冯鹏, 田野, 覃兆平. 纤维增强复合材料拉挤型材桁架桥静动力性能研究[J]. 工业建筑, 2013, 43(6):36-41.FENG peng, TIAN Ye, QIN Zhaoping. Static and dynamic behevior of a truss bridge made of pultruded profiles[J]. Industrial Construction,2013,43(6):36-41(in Chinese). [11] FANG H, BAI Y, LIU W Q, et al. Connections and structural applications of fibre reinforced polymer composites for civil infrastructure in aggressive environments[J]. Composites Part B: Engineering,2019,164:129-143. doi: 10.1016/j.compositesb.2018.11.047 [12] ZHANG T, LUO W, XIAO W, et al. Numerical simulation of single-lap adhesive joint of composite laminates[J]. Jour-nal of Reinforced Plastics and Composites,2018,37(8):520-532. doi: 10.1177/0731684418754358 [13] SHANG X, MARQUES E, CARBAS R, et al. Fracture mechanism of adhesive single-lap joints with composite adherends under quasi-static tension[J]. Composite Structures,2020,251:112639. [14] 刘玉擎, 都骜, 辛灏辉, 等. 拉挤GFRP型材层合板螺栓连接试验[J]. 中国公路学报, 2017, 30(6):223-229. doi: 10.3969/j.issn.1001-7372.2017.06.005LIU Yuqing, DU Ao, XIN Haohui, et al. Experiment on bolted joints of pultruded GFRP laminates[J]. China Jour-nal of Highway and Transport,2017,30(6):223-229(in Chinese). doi: 10.3969/j.issn.1001-7372.2017.06.005 [15] 毛振刚, 侯玉亮, 李成, 等. 搭接长度和铺层方式对CFRP复合材料层合板胶接结构连接性能和损伤行为的影响[J]. 复合材料学报, 2020, 37(1):121-131.MAO Zhen'gang, HOU Yuliang, LI Cheng, et al. Effect of lap length and stacking sequence on strength and damage behaviors of adhesively bonded CFRP composite laminates[J]. Acta Materiae Compositae Sinica,2020,37(1):121-131(in Chinese). [16] CHENG X, WANG S, ZHANG J, et al. Effect of damage on failure mode of multi-bolt composite joints using failure envelope method[J]. Composite Structures,2017,160:8-15. doi: 10.1016/j.compstruct.2016.10.042 [17] 赵丽滨, 徐吉峰. 先进复合材料连接结构分析方法[M]. 北京: 北京航空航天大学出版社, 2015.ZHAO Libin, XU Jifeng. Analytical methods for advanced composite joint structures[M]. Beijing: Beihang University Press, 2015(in Chinese). [18] LI J, YAN Y, ZHANG T, et al. Experimental study of adhesively bonded CFRP joints subjected to tensile loads[J]. International Journal of Adhesion and Adhesives,2015,57:95-104. doi: 10.1016/j.ijadhadh.2014.11.001 [19] PALMIERI F L, BELCHER M A, WOHL C J, et al. Laser ablation surface preparation for adhesive bonding of carbon fiber reinforced epoxy composites[J]. International Jour-nal of Adhesion and Adhesives,2016,68:95-101. doi: 10.1016/j.ijadhadh.2016.02.007 [20] 蒋正文. GFRP桥面板胶接界面力学性能研究[D]. 南京: 东南大学, 2018.JIANG Zhengwen. Research of mechanical properties for adhesively bonded joint in gfrp bridge deck[D]. Nanjing: Southeast University, 2018(in Chinese). [21] GIANNOPOULOS I K, DORONIDAWES D, KOUROUSIS K I, et al. Effects of bolt torque tightening on the strength and fatigue life of airframe FRP laminate bolted joints[J]. Composites Part B: Engineering,2017,125(12):19-26. [22] ROMANOV V S, HEIDARI RARANI M, LESSARD L. A parametric study on static behavior and load sharing of multi-bolt hybrid bonded/bolted composite joints[J]. Compo-sites Part B: Engineering,2021,217:108897. doi: 10.1016/j.compositesb.2021.108897 [23] ZHAO L B, FANG Z, LIU F R, et al. A modified stiffness method considering effects of hole tensile deformation on bolt load distribution in multi-bolt composite joints[J]. Composite Part B: Engineering,2019,171:264-271. doi: 10.1016/j.compositesb.2019.05.010 [24] LIU F, LU X, ZHAO L, et al. Investigation of bolt load redistribution and ts effect on failure prediction in double-lap, multi-bolt composite joints[J]. Composite Structures,2018,202(10):397-405. [25] LIU F, FANG Z, ZHAO L, et al. A failure-envelope-based method for the probabilistic failure prediction of compo-site multi-bolt double-lap joints[J]. Composites Part B: Engineering,2019,172:593-602. doi: 10.1016/j.compositesb.2019.05.034 [26] 房子昂, 赵丽滨, 刘丰睿, 等. 碳纤维/树脂复合材料多钉连接钉载系数测试方法[J]. 复合材料学报, 2019, 36(12):2795-2804.FANG Ziang, ZHAO Libin, LIU Fengrui, et al. Tesing method of bolt load distribution in carbon fiber/resin compo-site multi-bolt joints[J]. Acta Materiae Compositae Sinica,2019,36(12):2795-2804(in Chinese). [27] 龚潇. 碳纤维复合材料机械连接载荷分配均匀化研究[D]. 上海: 上海交通大学, 2015.GONG Xiao. Research on the equalization of load distribution of carbon fibre composite bolt joints[D]. Shanghai: Shanghai Jiao Tong University, 2015(in Chinese). [28] 赵美英. 复合材料机械连接失效分析及强度影响因素研究[D]. 西安: 西北工业大学, 2006.ZHAO Meiying. Study on the failure analysis and strength influencing factors of composite mechanical connec-tions[D]. Xi’an: Northwestern Polytechnical University, 2006(in Chinese). [29] 谢宗蕻, 李想, 郭家平, 等. 考虑间隙配合的复合材料钉载分配均匀化方法[J]. 复合材料学报, 2016, 33(4):806-813.XIE Zonghong, LI Xiang, GUO Jiaping, et al. Load distribution homogenization method of multi-bolt composite joint with consideration of bolt-hole clearance[J]. Acta Materiae Composite Sinica,2016,33(4):806-813(in Chinese). [30] 李想, 谢宗蕻. 复合材料多钉连接钉载分配均匀化的泰勒展开方法[J]. 哈尔滨工业大学学报, 2019, 51(11):108-115. doi: 10.11918/j.issn.0367-6234.201811201LI Xiang, XIE Zonghong. A taylor expansion algorithm for the load distribution homogenization of multi-bolt composite joints[J]. Journal of Harbin Institute of Technology,2019,51(11):108-115(in Chinese). doi: 10.11918/j.issn.0367-6234.201811201 [31] 赵启林, 高一峰, 李飞. 复合材料预紧力齿连接技术研究现状与进展[J]. 玻璃钢/复合材料, 2014(12):52-56.ZHAO Qilin, GAO Yifeng, LI Fei. Current research and development of the application of the pre-tightened tooth connection[J]. Fiber Reinforced Plastics/Composites,2014(12):52-56(in Chinese). [32] ZHAO Q L, LI F, GAO Y F, et al. Research on the shear failure load of composite pre-tightened tooth connections by the characteristic lengths[J]. Journal of Reinforced Plastics and Composites,2015,34(14):1153-1166. doi: 10.1177/0731684415588935 [33] ZHANG D D, ZHAO Q L, HUANG Y X, et al. Flexural properties of a lightweight hybrid FRP-aluminum modular space truss bridge system[J]. Composite Structures,2014,108:600-615. [34] ZHANG D D, ZHAO Q L, LI F, et al. Torsional behavior of a hybrid FRP-aluminum space truss bridge: Experimental and numerical study[J]. Engineering Structures,2018,157:132-143. [35] ZHANG D D, LV Y R, ZHAO Q L, et al. Development of lightweight emergency bridge using GFRP-metal composite plate-truss girder[J]. Engineering Structures,2019,196:109291. [36] ZHANG D D, YUAN J X, ZHAO Q L, et al. Static perfor-mance of a new GFRP-metal string truss bridge subjected to unsymmetrical loads[J]. Steel and Composite Structures,2020,35(5):641-657. [37] 李飞. 复合材料新型连接技术及在桁架中的应用研究[D]. 南京: 解放军理工大学, 2012.LI Fei. Research on new type of pultruded composite connection and application in the truss [D]. Nanjing: PLA University of Science and Technology, 2012(in Chinese). [38] LI F, ZHAO Q L, GAO Y F, et al. A prediction method of the failure load and failure mode for composite pre-tightened tooth connections based on the characteristic lengths[J]. Composite Structures,2016,154:684-693. doi: 10.1016/j.compstruct.2016.06.036 [39] LI F, ZHAO Q L, CHEN H S, et al. Experimental investigation of novel pre-tightened teeth connection technique for composite tube[J]. Steel and Composite Structures,2017,23(2):161-172. doi: 10.12989/scs.2017.23.2.161 [40] LI F, LIU Z, DUAN J H, et al. Research on failure mode and load distribution pattern of composite pretightened tooth connections under different tooth shapes[J]. Engineering Failure Analysis,2020,118:104801. doi: 10.1016/j.engfailanal.2020.104801 [41] GAO Y F, LI F, ZHAO Q L, et al. Failure modes and failure mechanisms of single tooth bound to composite pre-tightened tooth connection[J]. Journal of Reinforced Plastics and Composites,2018,37(4):267-283. doi: 10.1177/0731684417741205 [42] GAO Y F, LI F, ZHAO Q L, et al. Strength prediction of a single tooth bound to composite pre-tightened tooth connection (PTTC) joints based on different failure criteria[J]. KSCE Journal of Civil Engineering,2019,23(8):3547-3559. doi: 10.1007/s12205-019-1988-8 [43] 高一峰. 基于剪切非线性的复合材料预紧力齿连接强度与失效分析[D]. 南京: 陆军工程大学, 2019.GAO Yifeng. Strength and failure analysis of composite pre-tightened teeth connection based on shear nonlinearity[D]. Nanjing: Army Engineering University of PLA, 2019(in Chinese). [44] 高建岗. 拉挤型复合材料预紧力齿连接件疲劳失效机理及寿命预测方法研究[D]. 南京: 陆军工程大学, 2020.GAO Jiangang. Study on fatigue failure mechanism and life prediction method of pultruded composite pre-tightened teeth connection[D]. Nanjing: Army Engineering University of PLA, 2020(in Chinese). [45] 柳锦春, 高建岗, 赵启林, 等. 碳纤维增强树脂基复合材料预紧力单齿接头的静态及疲劳性能试验[J]. 复合材料学报, 2016, 33(10):2215-2222.LIU Jinchun, GAO Jiangang, ZHAO Qilin, et al. Tests for static and fatigue performances of carbon fiber reinforced plastics pre-tightened single tooth connector[J]. Acta Materiae Compositae Sinica,2016,33(10):2215-2222(in Chinese). [46] LIU J C, GAO J G, ZHAO Q L. Failure modes of CFRP pre-tightened single tooth joints under axial cyclic tensile loading[J]. Construction and Building Materials,2019,222:786-795. doi: 10.1016/j.conbuildmat.2019.06.206