Research on Pull-out Test and Stress Model of UHPC Reinforced with GFRP Bent Bars
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摘要: 通过玻璃纤维增强复合材料(GFRP)弯折筋增强超高性能混凝土(UHPC)拉拔试验,研究了GFRP筋弯折区域力学服役性能及损伤机制,揭示了GFRP弯折筋与UHPC协同受力状态,建立了试件受力模型。试验研究变量包括:GFRP筋材直径、弯折筋尾部锚固长度、筋材尾部形状以及筋材基体种类。研究表明,受到GFRP筋材弯折区域褶皱和受力肩应力集中影响,GFRP筋材直径对弯折强度影响较大;弯折筋尾部锚固长度的增加,在一定程度上利于GFPR筋弯折强度提升;筋材尾部形状(L型和U型)对弯折强度的影响较小。基于此,阐述了GFRP筋弯折区在受拉状态下的损伤破坏机理;提出了GFRP弯折筋三阶段断裂过程:筋材受力肩内侧基体开裂、内侧纤维断裂和外侧纤维断裂;建立了GFRP弯折筋-UHPC弯折区域拉拔状态下的受力分析模型。Abstract: Through the pull-out test of Glass Fiber Reinforced Polymer(GFRP) bent bars reinforced Ultra High Performance Concrete(UHPC), the mechanical performance and damage mechanism of GFRP bars in bending zone were studied. The cooperative performance of GFRP bent bars and UHPC was revealed. The stress model of specimens was established. The study variables include: diameter of GFRP bars, anchoring length of the tail end of bent bars, shapes of the tail ends of bars and types of bar matrix. The results showed that the diameter of GFRP bars had a great influence on the bending strength due to the influence of the fold in the bending area and the stress concentration on the shoulder. The increase of the anchoring length at the tail of the GFRP bars had an positive effect on the bending strength of GFPR bars within a certain range, while the shape of tail end (L-shaped and U-shaped) bars had a little influence on the bending strength. The failure mechanism of GFRP bars under tension in the bending zone was presented, and three stages of fracture process of GFRP bars were revealed: the matrix cracking at the inside of stressed shoulders of bars, the inner fiber cracking and the outer fiber cracking. A stress analysis model was established for the bending area of GFRP-UHPC in the pull-out state.
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Key words:
- GFRP bent bar /
- UHPC /
- diameter of rebar /
- anchoring length /
- three-stage fracture model /
- stress model
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[1] 黄健,阎亮,熊哲,等. 新型GFRP-钢复合筋材料拉伸性能测试[J].工业建筑,2024,54(4):219-227. [2] 翟国良,汪海波,吴捷豪,等. 动荷载作用下FRP-混凝土-钢管组合结构能耗研究[J]. 工业建筑,2023,53(增刊1):340-343. [3] 蒋凯,杨元璋,赵唯坚. FRP箍筋弯角强度预测模型评估[J]. 工业建筑,2023,53(增刊1):595-599. [4] 张石,张爱林,张艳霞,等. 碳纤维增强复合材料筋混凝土框架结构动力性能试验研究[J]. 工业建筑,2023,53(2):92-98,91. [5] 丁小波,吴美仲,方五军,等.碳纤维增强复合材料条带箍筋混凝土梁剪切疲劳性能试验研究[J].工业建筑,2023,53(6):202-208,42. [6] 王静阳,刘荣进,陈平,等. 内养护剂对UHPC体积稳定性的影响[J]. 工业建筑,2023,53(增刊2):713-716,703. [7] 王会杰,李红卫,郝梅,等. 超高性能混凝土研究与应用[J]. 工业建筑,2023,53(增刊1):672-674. [8] 辛灏辉. GFRP桥面板材料-结构一体化设计研究[D]. 上海:同济大学,2017. [9] 阎培渝. 超高性能混凝土(UHPC)的发展与现状[J]. 混凝土世界,2010(9):36-41. [10] 肖锐,邓宗才,申臣良. 超高性能混凝土(UHPC)材料与构件设计[J]. 特种结构,2013(2):114-120. [11] HAN S, FAN C, ZHOU A, et al. Shear behavior of concrete beams reinforced with corrosion-resistant and ductile longitudinal steel-FRP composite bars and FRP stirrups[J]. Engineering Structures, 2023, 278,115520. [12] SARIKAYA H, BALCIOĞLU H. The effect of glass fiber rebar reinforcement on the flexural behavior of reinforced concrete structural elements[C]//Conference: IV. International Ege Composite Materials Symposium. Izmir: Ege University, 2018: 725-735. [13] 白浩阳,薛伟辰,江佳斐.基于数据库的玻璃纤维增强复合材料箍筋弯拉强度计算方法[J].哈尔滨工程大学学报,2024,45(2):223-229. [14] ZHOU L Z, ZHENG Y, DI B, et al. Shear behaviour of SWSS-SCC beams reinforced with GFRP bars and stirrups: experimental and analytical investigations[J]. Structures, 2023, 56,104946. [15] ZHAO J, BAO X, YANG S, et al. Experimental and theoretical studies on the shear performance of concrete beams reinforced with fiber-reinforced polymer stirrups[J/OL]. Materials, 2024, 17[2024-04-16]. https://doi.org/10.3390/ma17030593. [16] ZHAO W J, JIANG K, YANG Y Z. Numerical simulation of bent corner of FRP stirrups with rectangular cross sections[J/OL]. Journal of Structural Engineering, 2023, 149[2024-04-16]. https://doi.org/10.1061/JSENDH.STENG-11950. [17] 蒋济同,高瑜. FRP筋混凝土梁抗剪性能研究综述[J]. 复合材料科学与工程,2023(12):119-128. [18] 江佳斐,吕佳豪,薛伟辰.FRP箍筋强度保留率分布模型与可靠性分析[J/OL].建筑材料学报,2024[2024-06-07].http://kns.cnki.net/kcms/detail/31.1764.TU.20231212.1657.003.html. [19] YUAN F, WANG Y, LI P, et al. Shear behaviour of seawater sea-sand coral aggregate concrete beams reinforced with FRP strip stirrups[J]. Engineering Structures, 2023, 290,116332. [20] American Society for Testing and Materials. Standard specification for solid round glass fiber reinforced polymer bars for concrete reinforcement: ASTM D7957/D7957M-17[S]. West Conshohocken: ASTM International, 2017. [21] TOMLINSON D, FAM A. Performance of concrete beams reinforced with basalt FRP for flexure and shear[J/OL]. Journal of Composites for Construction, 2014, 19(2)[2024-04-16]. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000491. [22] Canadian Standards Association (CSA). Specification for fibre-reinforced polymers (CAN/CSA S807∶19) [S]. Toronto: CSA Group, 2019. [23] EL-SAYED A K, EL-SALAKAWY E, BENMOKRANE B. Mechanical and structural characterization of new carbon FRP stirrups for concrete members[J]. Journal of Composites for Construction, 2007, 11(4):352-362. [24] 宋岩超,蒋济同.新型封闭式复丝缠绕CFRP箍筋抗拉强度正交试验研究[J/OL].复合材料科学与工程,2024[2024-06-07].http://kns.cnki.net/kcms/detail/10.1683.tu.20240229.1612.003.html. [25] 汪国贤,李明,张黎飞,等. GFRP箍筋弯折强度试验及理论研究[J]. 公路与汽运,2021(6):131-136. [26] CHOLOSTIAKOW S, DI BENEDETTI M, PILAKOUTAS K, et al. Experimental analysis of shear resisting mechanisms in FRP RC beams with shear reinforcement[J/OL]. Journal of Composites for Construction, 2020, 24(5)[2024-01-30]. https://doi.org/10.1061/(ASCE)CC.1943-5614.0001046.
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