Shear Performance of Reinforced Concrete Composite Beams Without Stirrups with Use of Engineered Cementitious Composite Stay-in-Place Formwork
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摘要:
为研究工程水泥基复合材料（ECC）免拆模板对RC无腹筋组合梁抗剪性能的影响，以ECC免拆模板厚度和界面条件为试验参数，开展ECC材料力学性能试验及ECC免拆模板RC无腹筋组合梁四点弯曲加载试验. 首先，对ECC材料的抗拉与抗压力学性能进行试验研究；其次，基于材料试验结果，分别设计1根普通RC无腹筋梁和6根U型ECC免拆模板RC无腹筋组合梁，其中组合梁考虑2类界面条件（光滑与均布剪力键）和3种U型模板厚度（15、20、25 mm），并对这7根梁进行四点加载破坏试验；最后，基于修正桁架模型理论，提出ECC免拆模板RC无腹筋组合梁的抗剪承载力计算公式. 试验结果表明：ECC材料在单轴单调加载条件下表现出拟应变硬化特性及多条微细裂缝分布行为，其屈服抗拉强度和极限抗拉强度分别达到2 MPa和3 MPa以上，断裂拉伸应变超过2.0%；组合梁的抗剪承载力和变形能力相较于同尺寸配筋的RC无腹筋梁分别提升至少55.6%和113.0%，其中，20 mm厚ECC模板的组合梁抗剪承载力最高，界面条件对承载力影响不显著但均布剪力键可减小跨中挠度；提出的理论计算公式与试验数据吻合良好. 本文结论基于特定尺寸的实验室模型梁得出，在实际工程应用中需注意材料与构件的缩尺效应影响.
Abstract:To investigate the influence of engineered cementitious composite (ECC) stay-in-place formwork on the shear performance of reinforced concrete (RC) composite beams without stirrups, mechanical tests on the ECC material and four-point bending tests on RC composite beams without stirrups with the use of ECC stay-in-place formwork were conducted, with the thickness of the ECC stay-in-place formwork and the interface condition taken as the test parameters. First, the tensile and compressive mechanical properties of the ECC material were experimentally examined. Then, based on the material test results, one conventional RC beam without stirrups and six RC composite beams without stirrups with the use of U-shaped ECC stay-in-place formwork were designed. For the composite beams, two interface conditions, namely smooth interface and uniformly distributed shear keys, and three U-shaped formwork thicknesses (15, 20, and 25 mm) were considered. Four-point loading failure tests were carried out on all seven beams. Finally, based on the modified truss model theory, a formula for calculating the shear capacity of RC composite beams without stirrups with the use of ECC stay-in-place formwork was proposed. The test results indicate that under uniaxial monotonic loading, the ECC material exhibits pseudo strain-hardening characteristics and multiple fine cracks, with the yield tensile strength and ultimate tensile strength exceeding 2 MPa and 3 MPa, respectively, and the tensile strain at break exceeding 2.0%. Compared with the RC beam without stirrups which has the same dimensions and reinforcement, the composite beams show increases of at least 55.6% and 113.0% in shear capacity and deformation capacity, respectively. The composite beam with a 20 mm-thick ECC formwork exhibits the highest shear capacity. Although the interface condition has no significant effect on the shear capacity, the uniformly distributed shear keys can reduce the mid-span deflection. The proposed theoretical formula agrees well with the experimental data. The conclusions of this study are based on laboratory model beams of specific dimensions. Therefore, the scale effects of materials and structural members should be taken into account in practical engineering applications.
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图 3 实验梁截面尺寸与配筋
Figure 3. Cross-sectional dimensions and reinforcement details of test beams
图 9 ES梁的ECC模板与混凝土的横向脱粘
Figure 9. Transverse debonding between ECC formwork and concrete in ES beams
图 15 组合梁抗剪承载力计算值与实测值对比
Figure 15. Comparison between calculated and measured values of shear capacity for composite beams
表 1 PP纤维特性
Table 1. Properties of polypropylene （PP） fibers
长度
/mm直径
/μm弹性模量
/GPa抗拉强度
/MPa密度
/（g•cm−3）12 36 5 482 0.92 
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表 3 纵筋抗拉性能
Table 3. Tensile properties of longitudinal bars
直径
/mm屈服强度
/MPa抗拉强度
/MPa伸长率
/%18 456.14 600.24 29.0
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表 4 临界斜裂缝开裂角度
Table 4. Angles of critical inclined cracks
ES-15 ES-20 ES-25 EK-15 EK-20 EK-25 37.9° 39.9° 57.4° 37.9° 39.5° 44.7°
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表 5 加载试验结果汇总
Table 5. Summary of loading test results
梁 Vexp/KN 跨中挠度/mm RC-ref 39.41 2.92 ES-15 61.79 6.76 ES-20 69.06 11.31 ES-25 61.31 7.98 EK-15 64.55 6.21 EK-20 68.83 6.48 EK-25 67.40 7.11 注：Vexp为梁的抗剪承载力试验值.
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表 6 组合梁的计算剪力分担值
Table 6. Calculated shear sharing values of composite beams
试件 Vc
/kNVf
/kNVecc_cal
（kN）Vecc
（kN）ES-15 8.94 16.07 25.0 27.44 ES-20 10.90 20.11 31.0 36.34 ES-25 12.73 16.87 29.6 30.32 EK-15 8.94 16.07 25.0 30.20 EK-20 10.90 20.11 31.0 36.11 EK-25 12.73 16.87 29.6 36.41
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[1] 杜荣军. 混凝土工程模板与支架技术[M]. 3 版. 北京: 机械工业出版社, 2004. [2] 王彤. 永久模板与现浇混凝土叠合梁的试验研究[D]. 长春: 吉林大学, 2012. [3] 杨嗣信. 建筑工程模板施工手册[M]. 3. 版. 北京: 中国建筑工业出版社, 1997. [4] Wringley R. G. Permanent formwork in construction (CIRIA C558) [R], London: CIRIA/Concrete Society, 2001. [5] 刘永军, 丁文艺, 刘畅. 永久性模板的技术发展[J]. 水利与建筑工程学报, 2010, 8(6): 30-34.Liu Yongjun, Ding Wenyi, Liu Chang. Technical development of permanent template[J]. Journal of Water Resources and Architectural Engineering, 2010, 8(6): 30-34. [6] Kim G B, Pilakoutas K, Waldron P. Development of thin FRP reinforced GFRC permanent formwork systems[J]. Construction and Building Materials, 2008, 22(11): 2250-2259. doi: 10.1016/j.conbuildmat.2007.07.029 [7] 董伟, 泽里罗布, 银英姿, 等. 玄武岩纤维风积沙混凝土单轴受压应力-应变试验研究[J]. 西南交通大学学报, 2026, 61(1): 65-73.Dong Wei, Ze Liluobu, Yin Yingzi, et al. Experimental study on uniaxial compressive stress–strain of basalt fiber aeolian sand concrete[J]. Journal of Southwest Jiaotong University, 2026, 61(1): 65-73. [8] 黄志超, 张宗宇, 苏谦, 等. 无砟轨道玄武岩纤维泡沫混凝土路基动力特性分析[J]. 西南交通大学学报, 2025, 60(6): 1424-1432.Huang Zhichao, Zhang Zongyu, Su Qian, et al. Dynamic characteristic analysis of basalt fiber foam concrete subgrade for ballastless track[J]. Journal of Southwest Jiaotong University, 2025, 60(6): 1424-1432. [9] Naaman A E, Reinhardt H W. High performance fiber reinforced cement composites HPFRCC-4: International workshop Ann Arbor, Michigan, June 16–18, 2003[J]. Cement and Concrete Composites, 2004, 26(6): 757-759. doi: 10.1016/j.cemconcomp.2003.09.001 [10] 林上顺, 林永捷, 张建帅, 等. ECC和预制榫卯混合连接装配式桥墩抗震试验及计算方法[J]. 西南交通大学学报, 2025, 60(2): 472-483.Lin Shangshun, Lin Yongjie, Zhang Jianshuai, et al. Seismic testing and calculation method of assembled bridge piers with hybrid connection of engineered cementitious composites and assembled mortise-tenon joints[J]. Journal of Southwest Jiaotong University, 2025, 60(2): 472-483. [11] LI V C. Engineered cementitious composites – tailored composites through micromechanical modeling[C]//Fiber Reinforced Concrete: Present and the Future. Montreal: Canadian Society for Civil Engineering, 1998: 64-97. [12] Zhang R, Meng Q L, Shui Q J, et al. Cyclic response of RC composite bridge columns with precast PP-ECC jackets in the region of plastic hinges[J]. Composite Structures, 2019, 221: 110844. doi: 10.1016/j.compstruct.2019.04.016 [13] Kawashima K, Zafra R, Sasaki T, et al. Effect of polypropylene fiber reinforced cement composite and steel fiber reinforced concrete for enhancing the seismic performance of bridge columns[J]. Journal of Earthquake Engineering, 2011, 15(8): 1194-1211. doi: 10.1080/13632469.2011.569051 [14] Liu H Z, Zhang Q, Gu C S, et al. Self-healing of microcracks in Engineered Cementitious Composites under sulfate and chloride environment[J]. Construction and Building Materials, 2017, 153: 948-956. doi: 10.1016/j.conbuildmat.2017.07.126 [15] Maalej M, Ahmed S F U, Paramasivam P. Corrosion durability and structural response of functionally-graded concrete beams[J]. Journal of Advanced Concrete Technology, 2003, 1(3): 307-316. doi: 10.3151/jact.1.307 [16] Xu S L, Li Q H. Theoretical analysis on bending behavior of functionally graded composite beam crack-controlled by ultrahigh toughness cementitious composites[J]. Science in China Series E: Technological Sciences, 2009, 52(2): 363-378. doi: 10.1007/s11431-008-0337-9 [17] Li Q H, Xu S L. Experimental investigation and analysis on flexural performance of functionally graded composite beam crack-controlled by ultrahigh toughness cementitious composites[J]. Science in China Series E: Technological Sciences, 2009, 52(6): 1648-1664. doi: 10.1007/s11431-009-0161-x [18] LukoviĆ M, Hordijk D. A, HUANG Z, et al. Strain Hardening Cementitious Composite (SHCC) for crack width control in reinforced concrete beams[J]. Heron, 2019, 64(1/2): 189-206. [19] Qin F J, Wei X Y, Lu Y F, et al. Flexural behaviour of high strength engineered cementitious composites (ECC)-reinforced concrete composite beams[J]. Case Studies in Construction Materials, 2023, 18: e02002. doi: 10.1016/j.cscm.2023.e02002 [20] 王新颖, 姜冬雪, 鞠彦忠, 等. 基于桁架-拱模型的预制U形UHPC叠合梁抗剪承载力计算方法[J/OL]. 复合材料学报, 2025-08-07. https://doi.org/10.13801/j.cnki.fhclxb.20250807.001. [21] Qiao Z, Pan Z F, Xue W C, et al. Experimental study on flexural behavior of ECC/RC composite beams with U-shaped ECC permanent formwork[J]. Frontiers of Structural and Civil Engineering, 2019, 13(5): 1271-1287. doi: 10.1007/s11709-019-0556-0 [22] Qin F J, Zhang Z G, Yin Z W, et al. Use of high strength, high ductility engineered cementitious composites (ECC) to enhance the flexural performance of reinforced concrete beams[J]. Journal of Building Engineering, 2020, 32: 101746. doi: 10.1016/j.jobe.2020.101746 [23] 梁峰华. 预制U形ECC永久模板-后浇混凝土复合梁受弯性能研究[D]. 重庆: 重庆大学, 2022. [24] 乔治, 潘钻峰, 梁坚凝, 等. ECC/RC组合梁受弯性能试验研究与分析[J]. 东南大学学报(自然科学版), 2017, 47(4): 724-731.Qiao Zhi, Pan Zuanfeng, Leung C K Y, et al. Experimental study and analysis of flexural behavior of ECC/RC composite beams[J]. Journal of Southeast University (Natural Science Edition), 2017, 47(4): 724-731. [25] 曲春鹏. 预制U形ECC永久模板-后浇混凝土复合梁受剪性能研究[D]. 重庆: 重庆大学, 2022. [26] 郭莉英, 张伟, 邓明科, 等. 装配式超高延性混凝土免拆模板梁抗剪性能试验研究[J/OL]. 工程力学, 2025-11-11. https://kns.cnki.net/kcms/detail/detail.aspx?dbcode=CJFD&dbname=CJFD&filename=GCLX20251029006. [27] Ge W J, Ashour A F, Cao D F, et al. Experimental study on flexural behavior of ECC-concrete composite beams reinforced with FRP bars[J]. Composite Structures, 2019, 208: 454-465. doi: 10.1016/j.compstruct.2018.10.026 [28] Gu D W, Pan J L, Luković M. Understanding shear-resisting mechanism in reinforced engineered cementitious composite (ECC) beams using distributed strain measurements[J]. Engineering Structures, 2025, 327: 119612. doi: 10.1016/j.engstruct.2025.119612 [29] Wei X Y, Li X, Di J, et al. Flexural performance of U-shaped high-strength ECC permanent formwork-concrete composite beams[J]. Structures, 2025, 74: 108641. doi: 10.1016/j.istruc.2025.108641 [30] Japan Society of Civil Engineers (JSCE). Recommendations for Design and Construction of High Performance Fiber Reinforced Cement Composites with Multiple Fine Cracks (HPFRCC)[S]. Tokyo: JSCE, 2008(没有标准号Japan Society of Civil Engineers (JSCE). Recommendations for Design and Construction of High Performance Fiber Reinforced Cement Composites with Multiple Fine Cracks (HPFRCC)[S]. Tokyo: JSCE, 2008(没有标准号) [31] 张锐, 孟庆利, 何畏, 等. 考虑箍筋效应的PP-ECC梁抗剪试验研究[J]. 中国公路学报, 2017, 30(12): 234-241, 249.Zhang Rui, Meng Qingli, He Wei, et al. Experimental investigation on shear behavior of PP-ECC beams by considering effect of stirrup[J]. China Journal of Highway and Transport, 2017, 30(12): 234-241,249. [32] Niwa J, Yamada K, Yokozawa K, et al. Revaluation of the equation for shear strength of reinforced concrete beams without web reinforcement[J]. Doboku Gakkai Ronbunshu, 1986, 1986(372): 167-176. doi: 10.2208/jscej.1986.372_167 [33] Japan Society of Civil Engineers: Standard Specification for Concrete Structures (Structural Performance and Verification)[S]. Tokyo: Japan Society of Civil Engineers, 2018(没有标准号Japan Society of Civil Engineers: Standard Specification for Concrete Structures (Structural Performance and Verification)[S]. Tokyo: Japan Society of Civil Engineers, 2018(没有标准号) -
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