留言板

尊敬的读者、作者、审稿人, 关于本刊的投稿、审稿、编辑和出版的任何问题, 您可以本页添加留言。我们将尽快给您答复。谢谢您的支持!

姓名
邮箱
手机号码
标题
留言内容
验证码

ECC加固小偏心受压RC柱承载力

王新玲 李世伟 罗鹏程 范家俊

王新玲, 李世伟, 罗鹏程, 等. ECC加固小偏心受压RC柱承载力[J]. 复合材料学报, 2022, 40(0): 1-12
引用本文: 王新玲, 李世伟, 罗鹏程, 等. ECC加固小偏心受压RC柱承载力[J]. 复合材料学报, 2022, 40(0): 1-12
Xinling WANG, Shiwei LI, Pengcheng LUO, Jiajun FAN. Bearing capacity of RC columns strengthened by ECC under small eccentric compression load[J]. Acta Materiae Compositae Sinica.
Citation: Xinling WANG, Shiwei LI, Pengcheng LUO, Jiajun FAN. Bearing capacity of RC columns strengthened by ECC under small eccentric compression load[J]. Acta Materiae Compositae Sinica.

ECC加固小偏心受压RC柱承载力

基金项目: 国家自然科学基金面上项目(51879243);国家自然科学基金青年项目(52108183) ;中国博士后科学基金资助项目(2021 TQ0302);郑州大学青年人才企业合作创新团队项目(32320407).
详细信息
    通讯作者:

    范家俊,博士,讲师,从事新型复合材料性能及结构加固研 Email:jiajun.fan@zzu.edu.cn

  • 中图分类号: TU528.57

Bearing capacity of RC columns strengthened by ECC under small eccentric compression load

Funds: The National Natural Science Foundation of China(51879243); The National Natural Science Foundation of China (52108183); China Postdoctoral Science Foundation(2021 TQ0302); ZhengZhou University Young talents Enterprise Cooperative Team Innovation Project(32320407).
  • 摘要: 通过对工程水泥基复合材料(ECC)加固钢筋混凝土(RC)柱和未加固RC柱进行小偏心受压试验,研究ECC加固RC柱小偏心受压性能。试验结果表明,ECC加固层能有效约束核心混凝土;与未加固柱相比,加固柱的裂缝细而密,达到峰值荷载时受压区ECC尚未被压碎,破坏过程比较平缓,有较好的完整性,并表现出一定的延性特征;相对偏心距相同时,加固柱的开裂荷载、峰值荷载及延性相比未加固柱分别提高了107%~236%、45%~159%、37.4%~41.3%。依据试验结果,绘制出各加固柱跨中荷载-挠度曲线,可分为4个阶段:弹性阶段、裂缝稳定扩展阶段、最大荷载阶段及下降段。随着加固层厚度的增大,相同荷载下ECC竖向应变及钢筋应变越小;随着相对偏心距的增大,相同荷载下ECC竖向应变及钢筋应变越大。基于混凝土结构理论及力学原理,分析ECC加固层对核心混凝土柱的约束机制,提出ECC约束混凝土抗压强度和峰值应变的表达式,推导出加固柱受压承载力计算公式,承载力计算值与试验值相对误差在10%以内,二者吻合良好,为ECC加固混凝土柱在实际工程中的应用提供理论参考。

     

  • 图  1  ECC加固RC柱基本尺寸及截面配筋详图(单位:mm)

    Figure  1.  Basic dimensions and section reinforcement details of RC columns strengthened by ECC (Unit: mm)

    图  2  ECC加固RC柱示意图(单位:mm)

    Figure  2.  Schematic diagram of RC columns strengthened by ECC (Unit: mm)

    图  3  ECC典型受拉应力-应变曲线

    Figure  3.  ECC typical tensile stress-strain curve

    图  4  ECC加固RC柱加载装置示意图

    Figure  4.  Schematic diagram of ECC reinforced RC column loading device

    图  5  未加固RC柱加载及破坏形态

    Figure  5.  Unreinforced RC column loading setup and failure mode

    图  6  典型ECC加固RC柱裂缝发展分布及破坏图

    Figure  6.  Photograph of crack development and distribution diagram of typical RC columns strengthened by ECC

    图  7  ECC加固RC柱荷载-跨中挠度曲线

    Figure  7.  Load - mid-span deflection curves of RC columns strengthened by ECC

    图  8  ECC加固RC柱荷载-纵筋应变曲线

    Figure  8.  Load-longitudinal reinforcement strain curve of RC columns strengthened by ECC

    图  9  ECC加固RC柱荷载-ECC(混凝土)竖向应变曲线

    Figure  9.  Load-ECC vertical strain curves of RC columns strengthened by ECC

    图  10  ECC加固RC柱的延性指标定义

    Figure  10.  Definition of ductility index of ECC strengthened RC columns

    $\varDelta _y $ is the yield displacement; $\varDelta _u $ is the ultimate displacement; $ u$ is the ratio of the ultimate displacement to the yield displacement;

    图  11  ECC加固RC柱沿跨中截面的应变分布

    Figure  11.  Strain distribution along the mid-span section of RC columns strengthened by ECC

    图  12  ECC加固RC柱的开裂及峰值荷载与加固层厚度的关系曲线

    Figure  12.  Relationship between cracking and peak load of RC columns reinforced with ECC and the thickness of reinforcement layer

    图  13  ECC加固RC柱荷载-ECC横向应变曲线

    Figure  13.  Load-ECC transverse strain curves of RC columns strengthened by ECC

    图  14  ECC加固RC柱约束混凝土截面应力分析

    Figure  14.  Stress analysis of confined concrete section of RC column strengthened by ECC

    $ f_{j} $、 $ f_{k} $—Maximum lateral restraint force in the width and height directions of the section, respectively; $ f_{\text {et }} $—ECC horizontal tensile force of the reinforcement layer

    图  15  ECC加固RC柱小偏心受压计算模型

    Figure  15.  Calculation model of ECC reinforced RC column under small eccentric compression

    h0 , h1,0—Distance between the tension side reinforcement and the compression side edge of the concrete column and the compression side edge of the reinforced column; $A_{{\rm{s}}}$ , $A_{{\rm{s}}}^{\prime}$—Cross-section area of reinforcement on the tension side and compression side; e—Distance between the point of bearing capacity and the resultant point of longitudinal tension reinforcement; $ \sigma_{\mathrm{s}} $ , $\sigma_{{\rm{s}}}^{\prime}$—Stress value of reinforcement on the tension side and compression side; εs—Elastic modulus of reinforcement

    图  16  ECC加固RC柱界限破坏截面应变分布

    Figure  16.  Strain distribution of the balance failure section of ECC reinforced RC column

    $ \varepsilon_{\mathrm{y}} $—Yield tensile strain of the steel bar; $x_{{\rm{cb}}}$—Actual height of the compression zone of the limit failure

    表  1  ECC加固RC柱试件参数

    Table  1.   Test parameters of RC columns strengthened by ECC

    Groupb1×h1 /
    mm×mm
    H/mme0/mmt/mm
    RC200×25012000.22h10
    ECC-RCA1250×30012000.22h125
    ECC-RCA2270×32012500.22h135
    ECC-RCA3290×34013500.22h145
    ECC-RCB1250×30012000.3h125
    Notes: h1 is the section height of the reinforced column; b1 is the section width of the reinforced column; H is the height of the reinforced column; e0 is the eccentricity; t is the thickness of ECC reinforcement layer; A and B represent the relative eccentricity of 0.22 and 0.3, respectively; 1, 2, and 3 represent the thickness of the reinforcement layer of 25 mm, 35 m, and 45 mm, respectively.
    下载: 导出CSV

    表  2  ECC配合比(质量比)

    Table  2.   ECC mix ratio (Mass ratio)

    CementSandFly ashMicro-silicon powderWaterWater reducerPVA fiberThickener
    10.430.0731.020.040730.0720.00182
    下载: 导出CSV

    表  3  PVA纤维性能参数

    Table  3.   Performance index of PVA fiber

    Diameter /μmLength /mmTensile strength /MPaModulus of elasticity /GPaFracture elongation /%Density /( ${\rm{g}}\cdot $cm−3)
    40121560416.51.3
    下载: 导出CSV

    表  4  ECC抗压和抗拉试验结果

    Table  4.   ECC compressive and tensile test results

    GroupCompressive
    ultimate load/kN
    fe/MPafet/MPaUltimate
    tensile strain/%
    ECC-RCA1194.538.73.653.12
    ECC-RCA2187.737.53.633.19
    ECC-RCA3192.938.63.723.26
    ECC-RCB1181.836.43.703.18
    Notes: fe is the compressive strength of ECC; fet is the tensile strength of ECC.
    下载: 导出CSV

    表  5  ECC加固RC柱主要试验结果

    Table  5.   Main test results of RC columns strengthened by ECC

    Groupfco/MPafe/MPaNk/kNncrNp/kNn0De/mmnde
    RC29.6-1211.006001.002.161.00
    ECC-RCA128.438.72512.078681.453.821.77
    ECC-RCA229.837.53522.9113012.173.981.84
    ECC-RCA329.938.64063.3615522.594.211.95
    ECC-RCB129.735.51811.466611.106.032.79
    Notes: fco is the axial compressive strength of concrete; Nk is cracking load; ncr is the cracking load ratio of reinforced column and unreinforced column; Np is peak load; n0 is the peak load ratio between the reinforced column and the unreinforced column; De is the mid-span deflection corresponding to peak load; nde is the deflection ratio corresponding to the peak load of the reinforced column and the unreinforced column.
    下载: 导出CSV

    表  6  ECC加固RC柱延性指标的对比

    Table  6.   Comparison of ductility indexes of RC columns strengthened by ECC

    Group$ \varDelta _y /{\rm{mm}}$$ \varDelta _u /{\rm{mm}}$$ u=\varDelta _u/\varDelta _y $$ n_u$
    RC1.392.161.551.00
    ECC-RCA12.164.732.191.413
    ECC-RCA22.224.802.161.394
    ECC-RCA32.284.852.131.374
    ECC-RCB13.318.012.421.561
    Notes: nu is the ratio of the ductility coefficient between the reinforced column and the unreinforced column.
    下载: 导出CSV

    表  7  ECC加固RC柱峰值应变及约束效应系数

    Table  7.   Peak strain and restraint effect coefficient of ECC-reinforced RC columns

    Group$\varepsilon_{{\rm{s}}}'$/%$\varepsilon_{{\rm{ec}}}$/%$a_{\rm{s}}'$/mm$ t$/mm$\varepsilon_{{\rm{cc}}}$/%k2
    ECC-RCA10.2080.217240250.21472.629
    ECC-RCA20.1840.247740350.2242.634
    ECC-RCA30.17020.283640450.22682.635
    Notes: $ \varepsilon_{{\rm{s}}}'$ is the reinforcement strain on the compression side; $ \varepsilon_{{\rm{ec}}}$ is ECC strain on compression side; $ a_{\rm{s}}'$ is the thickness of RC column protection layer; $ \varepsilon_{{\rm{cc}}}$ is ECC confined peak compressive strain of concrete; k2 is strain constraint effect coefficient.
    下载: 导出CSV

    表  8  ECC加固RC柱承载力计算值与试验值比较

    Table  8.   Comparison between the calculated and experimental values of the bearing capacity of ECC-reinforced RC columns

    GroupNp-theo/kNNp-test/kNNp-theo/Np-test
    ECC-RCA19138681.052
    ECC-RCA2123613010.950
    ECC-RCA3147115520.948
    ECC-RCB16986611.056
    B2150516210.928
    Notes: Np-theo is the calculated value; Np-test is the test value.
    下载: 导出CSV
  • [1] LI Victor C, WANG Shu-xin, WU Cynthia. Tensile strain-hardening behavior of PVA-ECC[J]. ACI Materials Journal,2001,98(6):483-492.
    [2] Wu C, Leung CKY, Li VC. Derivation of Crack Bridging Stresses in Engineered Cementitious Composites under Combined Opening and Shear Displacements[J]. Cement and Concrete Research,2018,107:253-263. doi: 10.1016/j.cemconres.2018.02.027
    [3] 吴畅, 王欣汝, 许铭纹, 等. 基于梁理论的ECC拉伸应变硬化与多缝开裂行为的数值模拟[J]. 复合材料学报, 2022, 40(0):1-12.

    WU Chang, WANG Xinru, XU Mingwen, et al. Numerical simulation of the tensile strain hardening and multiple cracking behavior of ECC based on beam theory[J]. Acta Materiae Compositae Sinica,2022,40(0):1-12(in Chinese).
    [4] 王新玲, 李苗浩夫, 李可. ECC圆柱体轴心受压性能试验研究[J]. 建筑科学, 2019, 35(5):59-63.

    WANG Xinling, LI Miaohaofu, LI Ke. Experimental research on the axial compression performance of ECC cylinders[J]. Building Science,2019,35(5):59-63(in Chinese).
    [5] MKI Khan, MM Rana, YX Zhang, et al. Behaviour of engineered cementitious composite-encased stub concrete columns under axial compression[J]. Magazine of Concrete Research,2020,72(19):984-1005. doi: 10.1680/jmacr.19.00111
    [6] Mechtcherine V, Silva FDA, Müller S, et al. Coupled strain rate and temperature effects on the tensile behavior of strain-hardening cement-based composites (SHCC) with PVA fibers[J]. Cement and Concrete Research,2012,42(11):1417-1427. doi: 10.1016/j.cemconres.2012.08.011
    [7] Fischer G, Li VC. Effect of matrix ductility on deformation behavior of steel reinforced ECC flexural members under reversed cyclic loading conditions[J]. ACI Structural Journal,2002,99(6):781-790.
    [8] 王新玲, 李赟璞, 李苗浩夫, 等. 高强不锈钢绞线网增强ECC加固RC短柱轴心受压试验研究[J]. 复合材料学报, 2021, 38(0): 1-10.

    WANG Xinling, LI Yunpu, LI Miaohaofu, et al. Study on the compressive behavior of RC short columns strengthened with high-strength stainless steel wire strand mesh and ECC[J]. Acta Materiae Compositae Sinica. (in Chinese).
    [9] MKI Khan, MM Rana, YX Zhang, et al. Behaviour of engineered cementitious composite-encased stub concrete columns under axial compression[J]. Magazine of Concrete Research,2020,72(19):984-1005. doi: 10.1680/jmacr.19.00111
    [10] 袁超. 聚乙烯醇纤维水泥砂浆钢筋网加固RC偏压柱试验研究[D]. 湖南: 湖南大学, 2012.

    YUAN Chao. The research on bearing capaxity of PVA-ECC reinforced concrete square column subjected to eccentric load[D]. Hunan: Hunan University, 2012. (in Chinese).
    [11] 崔涛, 何浩祥, 闫维明, 等. ECC与既有混凝土结合面的抗剪性能[J]. 建筑材料学报, 2020, 23(5):1030-1037. doi: 10.3969/j.issn.1007-9629.2020.05.006

    CUI Tao, HE Weixiang, YAN Weiming, et al. Shear Resistance Property of ECC-Existing Concrete Interface[J]. Journal of Building Materials,2020,23(5):1030-1037(in Chinese). doi: 10.3969/j.issn.1007-9629.2020.05.006
    [12] 蔡景明, 潘金龙, 苏浩. 钢筋增强 ECC-钢管混凝土组合柱抗震性能试验及其数值模拟[J]. 建筑结构学报, 2020, 41(7):55-62.

    CAI Jingming, PAN Jinlong, SU Hao. Experimental and analytical research on seismic behavior of ECC-encased concrete-filled steel tubular columns[J]. Journal of Building Structures,2020,41(7):55-62(in Chinese).
    [13] 古音, 彭晨星. PVA-ECC加固桥墩抗震性能试验研究[J]. 振动与冲击, 2021.40(14): 92-99.

    GU Yin, PENG Chenxing, Experimental study on the seismic behavior of bridge piers strengthened with PVA-ECC[J]. Journal of Vibration and Shock, 2021.40(14): 92-99. (in Chinese)
    [14] 赵英驰, 冯锦鹏, 吴祥均. ECC管混凝土短柱轴心受压试验研究[J]. 重庆建筑, 2019, 18(6):28-31. doi: 10.3969/j.issn.1671-9107.2019.06.28

    ZHAO Yingchi, FENG Jinpeng, WU Xiangjun. Experimental research on axial compression of concrete short column of ECC tube[J]. Chongqing Architecture,2019,18(6):28-31(in Chinese). doi: 10.3969/j.issn.1671-9107.2019.06.28
    [15] 江佳斐, 隋凯. 纤维网格增强超高韧性水泥复合材料加固混凝土圆柱受压性能试验[J]. 复合材料学报, 2019, 8(36):1957-1967.

    JIANG Jiafei, SUI Kai. Experimental study of compression performance of concrete cylinder strengthened by textile reinforced engineering cement composites[J]. Acta Materiae Compositae Sinica,2019,8(36):1957-1967(in Chinese).
    [16] 龚宏伟, 江世永, 飞渭, 等. ECC结构抗震性能研究进展[J]. 玻璃钢/复合材料, 2019, 6(7):116-124.

    GONG Hongwei, JIANG Shiyong, FEI Wei, et al. Progress of study on seismic performance of ECC structures[J]. Fiber Reinforced Plastics/Composites,2019,6(7):116-124(in Chinese).
    [17] 中华人民共和国住房和城乡建设部. 混凝土结构加固设计规范: GB 50367-2013[S]. 北京: 中国建筑工业出版社, 2014.

    Ministry of housing and urban rural development of the peoples republic of china. Code for design of strengthening concrete structure: GB 50367-2013[S]. Beijing: China Architecture and Building Press, 2014. (in Chinese).
    [18] 刘伟康. ECC受压和受拉性能及本构模型研究[D]. 郑州: 郑州大学图书馆, 2018.

    LIU Weikang. Study on the Compression and tensile properties and the constitutive model of ECC[D]. Zhangzhou: Zhangzhou University Library, 2018. (in Chinese).
    [19] 中华人民共和国住房和城乡建设部. 混凝土结构试验方法标准: GB/T 50152-2012[S]. 北京: 中国建筑工业出版社, 2012.

    Ministry of housing and urban rural development of the peoples republic of china. Standard for test method of concrete structures: GB/T 50152-2012[S]. Beijing: China Architecture and Building Press, 2012. (in Chinese).
    [20] Bayrak O, Sheikh S A. Confinement reinforcement design considerations for ductile HSC columns[J]. Journal of Structural Engineering, ASCE,1998,124(9):999-1010. doi: 10.1061/(ASCE)0733-9445(1998)124:9(999)
    [21] 尚守平, 蒋隆敏, 张毛心. 钢筋网水泥复合砂浆加固RC偏心受压柱的试验研究[J]. 建筑结构学报, 2005, 26(2):18-25. doi: 10.3321/j.issn:1000-6869.2005.02.003

    ZHANG Shouping, JIANG Longmin, ZHANG Maoxin. Experimental investigation into the strengthening of eccentric compression RC column using composite mortar laminate reinforced with mesh reinforcement[J]. Journal of Building Structures,2005,26(2):18-25(in Chinese). doi: 10.3321/j.issn:1000-6869.2005.02.003
    [22] Mander J B, Priestley M J N, Park R J T. Theoretical stress-strain model for confined concrete[J]. Journal of Structural Engineering, ASCE,1998,114(8):1804-1826.
    [23] 卜良桃, 朱健, 陶剑剑, 侯奇. 活性粉末混凝土加固高强混凝土小偏压柱试验研究[J]. 建筑结构, 2014, 44(11):14-19.

    BU Liangtao, ZHU Jian, TAO Jianjian, et al. Experimental study on high-strength concrete columns reinforced by reactive powder concrete under small eccentric compressiott[J]. Building Structure,2014,44(11):14-19(in Chinese).
  • 加载中
计量
  • 文章访问数:  67
  • HTML全文浏览量:  25
  • 被引次数: 0
出版历程
  • 收稿日期:  2022-03-01
  • 录用日期:  2022-05-05
  • 修回日期:  2022-03-28
  • 网络出版日期:  2022-05-28

目录

    /

    返回文章
    返回