碳纤维约束高强混凝土圆柱压弯构件非线性全过程分析
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摘要
为分析塑性铰区碳纤维约束高强混凝土圆柱的抗震性能,编制了可得到荷载-位移曲线软化段的非线性全过程分析程序,保护层和箍筋约束混凝土采用Mander本构模型,碳纤维约束混凝土采用ACI 440.2R-08给出的本构关系,将程序计算结果与试验结果进行比较,两者吻合较好;利用该程序分析了轴压比、混凝土强度、碳纤维包裹长度及层数、纵筋配筋率等参数对碳纤维约束混凝土圆柱荷载-位移关系的影响规律,结果表明:当轴压比超过0.55后,柱构件的水平承载力开始降低,柱的破坏形式由延性的受拉破坏向脆性的受压破坏转变;剪跨比大于3的圆柱,碳纤维在塑性铰区包裹长度大于1.2倍柱直径时,即可达到与全柱包裹基本一致的效果;对混凝土强度为50 MPa~80 MPa的高强混凝土圆柱,以包裹3~4层碳纤维为宜;随着纵筋配筋率的增加,柱的水平极限承载力及延性均有所提高。
To analyze the seismic behavior of high strength concrete circular columns confined with carbon fiber sheets(CFS) in the plastic hinge region,a nonlinear analytical procedure was developed,which can obtain the descending branch of shear-tip deformation curves of columns subjected to axial load and lateral shear.The Mander stress-strain model was used for concrete confined with hoops and for unconfined concrete cover.The stress-strain model proposed by ACI 440.2R-08 was used for FRP-confined concrete.The numerical simulation results agree well with experimental results.Influences of axial compression ratio,concrete strength,height and layers of CFS wrapping,longitudinal reinforcement ratio on shear-tip deformation curves were analyzed using this procedure.The results indicate that the lateral loading capacity of columns begins to decrease when the axial compression ratio exceeds 0.55,and the failure mode of columns transfers from ductile tensile failure to brittle compressive failure.For columns with shear span ratio greater than 3.0,when the height of wrapped CFS in the plastic hinge region exceeds 1.2D(D is the diameter of circular column),the seismic performance can be improved to a level equivalent to full CFS-wrapped columns.For high strength concrete from 50MPa to 80MPa,three or four layers of CFS wrapping are reasonable.With an increase of the longitudinal reinforcement ratio,the shear capacity and ductility level of columns show a corresponding enhancement.
To analyze the seismic behavior of high strength concrete circular columns confined with carbon fiber sheets(CFS) in the plastic hinge region,a nonlinear analytical procedure was developed,which can obtain the descending branch of shear-tip deformation curves of columns subjected to axial load and lateral shear.The Mander stress-strain model was used for concrete confined with hoops and for unconfined concrete cover.The stress-strain model proposed by ACI 440.2R-08 was used for FRP-confined concrete.The numerical simulation results agree well with experimental results.Influences of axial compression ratio,concrete strength,height and layers of CFS wrapping,longitudinal reinforcement ratio on shear-tip deformation curves were analyzed using this procedure.The results indicate that the lateral loading capacity of columns begins to decrease when the axial compression ratio exceeds 0.55,and the failure mode of columns transfers from ductile tensile failure to brittle compressive failure.For columns with shear span ratio greater than 3.0,when the height of wrapped CFS in the plastic hinge region exceeds 1.2D(D is the diameter of circular column),the seismic performance can be improved to a level equivalent to full CFS-wrapped columns.For high strength concrete from 50MPa to 80MPa,three or four layers of CFS wrapping are reasonable.With an increase of the longitudinal reinforcement ratio,the shear capacity and ductility level of columns show a corresponding enhancement.
引文
[1]腾锦光,陈建飞,等.FRP加固混凝土结构[M].北京:中国建筑工业出版社,2005,144-229.(TENG Jin-guang,CHEN Jian-fei,et al.Strengthened RCStructures[M].Beijing:China Architecture&Build-ing Press,2005,144-229.(in Chinese))
[2]PRIESTLEY M J N,SEIBLE F,FYFE E.ColumnSeismic Retrofit Using Fibreglass/Epoxy Jackets[A].Advanced Composite Materials in Bridges andStructures[C].(Neale K.W.and Labossiere P.Ed.),1992.
[3]赵彤,刘明国,谢剑.碳纤维布用于改善斜向受力高强混凝土柱抗震性能的研究[J].土木工程学报,2002,35(3):13-19.(ZHAO Tong,LIU Ming-guo,XIE Jian.Study on the seismic behavior of high-strength concrete column with CFS subjected to axialcompression and biaxial bending[J].China Civil En-gineering Journal,2002,35(3):13-19.(in Chinese))
[4]张轲,岳清瑞.碳纤维布加固混凝土柱改善延性的试验研究[J].工业建筑,2000,30(2):16-19.(ZHANG Ke,YUE Qing-rui.Experimental researchon ductility improvement of concrete columnstrengthened with CFS[J].Industrial Construction,2000,30(2):16-19.(in Chinese))
[5]王伟,宋坤,王大鹏.纤维加固混凝土园截面短柱抗震性能试验研究[J].世界地震工程,2008,24(4):96-100.(WANG Wei,SONG Kun,WANG Da-peng.Experimental investigation on seismic perform-ance of CFRP retrofitted RC short columns with cir-cular section[J].World Earthquake Engineering,2008,24(4):96-100.(in Chinese))
[6]陶忠,于清,等.FRP约束钢筋混凝土圆柱力学性能的试验研究[J].建筑结构学报,2004,25(6):75-82.(TAO Zhong,YU Qing.Experimental behav-ior of FRP-confined circular RC columns[J].Journalof Building Structures,2004,25(6):75-82.(in Chi-nese))
[7]赵彤,刘明国,等.碳纤维布抗震加固斜向受力钢筋混凝土柱的非线性分析[J].世界地震工程,2001,17(4):53-59.(ZHAO Tong,LIU Ming-guo,et al.Nonlinear analysis of reinforced concrete columnswith carbon fiber sheet subjected to axial compressionand biaxial bending[J].World Information onEarthquake Engineering,2001,17(4):53-59.(inChinese))
[8]李静,钱稼茹.碳纤维布约束混凝土柱的非线性分析[J].工程力学,2005,22(1):159-163.(LI Jing,QIAN Jia-ru.Nonlinear analysis of carbon fiber sheetconfined concrete columns[J].Engineering Mechan-ics,2005,22(1):159-163.(in Chinese))
[9]吴波,王维俊,等.碳纤维布加固钢筋混凝土柱的弯矩-曲率关系分析[J].华南理工大学学报(自然科学版),2005,33(1):10-15.(WU Bo,WANG Wei-jun,et al.Analyses of the moment curvature rela-tionship of RC columns strengthened with carbon fi-ber sheets[J].Journal of South China University ofTechnology(Natural Science Edition),2005,33(1):10-15.(in Chinese))
[10]黄艳.碳纤维布加固混凝土墩柱抗震性能的分析[J].山西建筑,2008,34(15):60-61.(HUANG Yan.Seismic performance of concrete column confined byCFRP[J].Shanxi Architecture,2008,34(15):60-61.(in Chinese))
[11]MANDER J B,PRIESTLEY M J N.Theoreticalstress-strain model for confined concrete[J].Journalof Structural Engineering,1988,114(8):1805-1826.
[12]ACI Committee 440.Guide for the Design and Con-struction of Externally Bonded FRP Systems forStrengthening Concrete Structures[R].AmericanConcrete Institute,2008.
[13]LAM L,TENG J.Design-oriented stress-strainmodel for FRP-confined concrete[J].Constructionand Building Materials,2003,17:471-489.
[14]王震宇,芦学磊,李伟,等.塑性铰区碳纤维约束高强混凝土圆柱抗震性能的试验研究[J].建筑结构,2009,39(2):21-24.(WANG Zhen-yu,LU Xue-lei,LI Wei,et al.Experimental research on seismic per-formance of high strength concrete circular columnconfined with carbon fiber sheets at plastic hinge zone[J].Building Structure,2009,39(2):21-24.(in Chi-nese))
[15]高献,陶忠,杨有福,等.大轴压比下FRP约束混凝土柱滞回性能试验研究[J].工业建筑,2005,35(9):11-14.(GAO Xian,TAO Zhong,YANG You-fu,et al.Hysteretic behavior of circular RC columnsconfined with FRP jackets[J].Industrial Construc-tion,2005,35(9):11-14.(in Chinese))
[2]PRIESTLEY M J N,SEIBLE F,FYFE E.ColumnSeismic Retrofit Using Fibreglass/Epoxy Jackets[A].Advanced Composite Materials in Bridges andStructures[C].(Neale K.W.and Labossiere P.Ed.),1992.
[3]赵彤,刘明国,谢剑.碳纤维布用于改善斜向受力高强混凝土柱抗震性能的研究[J].土木工程学报,2002,35(3):13-19.(ZHAO Tong,LIU Ming-guo,XIE Jian.Study on the seismic behavior of high-strength concrete column with CFS subjected to axialcompression and biaxial bending[J].China Civil En-gineering Journal,2002,35(3):13-19.(in Chinese))
[4]张轲,岳清瑞.碳纤维布加固混凝土柱改善延性的试验研究[J].工业建筑,2000,30(2):16-19.(ZHANG Ke,YUE Qing-rui.Experimental researchon ductility improvement of concrete columnstrengthened with CFS[J].Industrial Construction,2000,30(2):16-19.(in Chinese))
[5]王伟,宋坤,王大鹏.纤维加固混凝土园截面短柱抗震性能试验研究[J].世界地震工程,2008,24(4):96-100.(WANG Wei,SONG Kun,WANG Da-peng.Experimental investigation on seismic perform-ance of CFRP retrofitted RC short columns with cir-cular section[J].World Earthquake Engineering,2008,24(4):96-100.(in Chinese))
[6]陶忠,于清,等.FRP约束钢筋混凝土圆柱力学性能的试验研究[J].建筑结构学报,2004,25(6):75-82.(TAO Zhong,YU Qing.Experimental behav-ior of FRP-confined circular RC columns[J].Journalof Building Structures,2004,25(6):75-82.(in Chi-nese))
[7]赵彤,刘明国,等.碳纤维布抗震加固斜向受力钢筋混凝土柱的非线性分析[J].世界地震工程,2001,17(4):53-59.(ZHAO Tong,LIU Ming-guo,et al.Nonlinear analysis of reinforced concrete columnswith carbon fiber sheet subjected to axial compressionand biaxial bending[J].World Information onEarthquake Engineering,2001,17(4):53-59.(inChinese))
[8]李静,钱稼茹.碳纤维布约束混凝土柱的非线性分析[J].工程力学,2005,22(1):159-163.(LI Jing,QIAN Jia-ru.Nonlinear analysis of carbon fiber sheetconfined concrete columns[J].Engineering Mechan-ics,2005,22(1):159-163.(in Chinese))
[9]吴波,王维俊,等.碳纤维布加固钢筋混凝土柱的弯矩-曲率关系分析[J].华南理工大学学报(自然科学版),2005,33(1):10-15.(WU Bo,WANG Wei-jun,et al.Analyses of the moment curvature rela-tionship of RC columns strengthened with carbon fi-ber sheets[J].Journal of South China University ofTechnology(Natural Science Edition),2005,33(1):10-15.(in Chinese))
[10]黄艳.碳纤维布加固混凝土墩柱抗震性能的分析[J].山西建筑,2008,34(15):60-61.(HUANG Yan.Seismic performance of concrete column confined byCFRP[J].Shanxi Architecture,2008,34(15):60-61.(in Chinese))
[11]MANDER J B,PRIESTLEY M J N.Theoreticalstress-strain model for confined concrete[J].Journalof Structural Engineering,1988,114(8):1805-1826.
[12]ACI Committee 440.Guide for the Design and Con-struction of Externally Bonded FRP Systems forStrengthening Concrete Structures[R].AmericanConcrete Institute,2008.
[13]LAM L,TENG J.Design-oriented stress-strainmodel for FRP-confined concrete[J].Constructionand Building Materials,2003,17:471-489.
[14]王震宇,芦学磊,李伟,等.塑性铰区碳纤维约束高强混凝土圆柱抗震性能的试验研究[J].建筑结构,2009,39(2):21-24.(WANG Zhen-yu,LU Xue-lei,LI Wei,et al.Experimental research on seismic per-formance of high strength concrete circular columnconfined with carbon fiber sheets at plastic hinge zone[J].Building Structure,2009,39(2):21-24.(in Chi-nese))
[15]高献,陶忠,杨有福,等.大轴压比下FRP约束混凝土柱滞回性能试验研究[J].工业建筑,2005,35(9):11-14.(GAO Xian,TAO Zhong,YANG You-fu,et al.Hysteretic behavior of circular RC columnsconfined with FRP jackets[J].Industrial Construc-tion,2005,35(9):11-14.(in Chinese))
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