【作者】 齐宏拓；

【导师】 张素梅； 刘界鹏；

【作者基本信息】 哈尔滨工业大学 ， 结构工程， 2014， 博士

【摘要】 钢管约束混凝土柱是在钢管混凝土柱、箍筋约束混凝土柱和型钢混凝土柱的基础上发展起来的一种新型组合结构构件，具有承载力高、延性好、抗火性能好、施工方便等优点。目前国内外对钢管约束混凝土柱的研究刚刚起步，以往的研究也主要集中在轴压短柱方面，而对工程中最为常见的偏压构件鲜有报道。本文对钢管约束混凝土偏压构件进行了试验研究及理论分析，主要内容包括：(1)进行了8个圆钢管约束钢筋混凝土轴压试件和16个圆钢管约束钢筋混凝土偏压试件试验研究，主要参数为长细比、偏心距及钢管约束模式。分析了不同钢管约束模式试件的破坏模式，测得了试件的荷载-位移曲线、荷载-钢管应力全过程曲线，建立了圆钢管约束钢筋混凝土偏压构件力学模型。建立了圆钢管约束钢筋混凝土偏压中长柱有限元模型，对圆钢管约束钢筋混凝土中长柱进行了全过程有限元分析。(2)进行了8个方钢管约束钢筋混凝土轴压试件和16个方钢管约束钢筋混凝土偏压试件试验研究，主要参数为长细比、偏心距及钢管约束模式。分析了不同钢管约束模式试件的破坏模式，测得了试件的荷载-位移曲线、荷载-钢管应力全过程曲线，建立了方钢管约束钢筋混凝土偏压构件力学模型。建立了方钢管约束钢筋混凝土偏压中长柱有限元模型，对方钢管约束钢筋混凝土中长柱进行了全过程有限元分析。(3)进行了12个圆钢管约束型钢混凝土轴压试件和12个圆钢管约束型钢混凝土偏压试件试验研究，主要参数为长细比、偏心距、钢管约束模式及不同的抗剪连接件设置方式。分析了不同钢管约束模式试件的破坏模式，测得了试件的荷载-位移曲线、荷载-钢管全过程应力曲线，分析了抗剪连接件的影响，建立了圆钢管约束钢筋混凝土偏压构件力学模型。建立了圆钢管约束钢筋混凝土偏压中长柱有限元模型，对圆钢管约束钢筋混凝土中长柱进行了全过程有限元分析。(4)进行了12个方钢管约束型钢混凝土轴压试件和12个方钢管约束型钢混凝土偏压试件试验研究，主要参数为长细比、偏心距、钢管约束模式及不同的抗剪连接件设置方式。分析了不同钢管约束模式试件的破坏模式，测得了试件的荷载-位移曲线、荷载-钢管应力全过程曲线，分析了抗剪连接件的影响，建立了方钢管约束钢筋混凝土偏压构件力学模型。建立了方钢管约束钢筋混凝土偏压中长柱有限元模型，对方钢管约束钢筋混凝土中长柱进行了全过程有限元分析。(5)采用基于Mander模型的约束混凝土本构关系，通过纤维模型法计算了试件的荷载-位移曲线；试验结果表明该模型适用于钢管约束混凝土构件，基于该模型计算了钢管约束混凝土的等效矩形应力。基于能量原理，计算了钢管约束混凝土极限压应变；基于钢管约束混凝土的等效矩形应力、钢管约束混凝土极限压应变，建立了钢管约束钢筋混凝土截面偏压承载力公式。采用切线模量法建议了钢管约束混凝土构件稳定系数，并基于约束混凝土本构关系建立了钢管约束混凝土构件偏心距增大系数计算方法。(6)基于截面全塑性假定，采用纤维模型法计算了钢管约束型钢混凝土偏压构件的N-M相关曲线，并采用曲线上的4个特征点，建立了钢管约束型钢混凝土截面偏压承载力简化计算公式；基于截面N-M相关曲线，通过折减弯矩的方法，提出了构件N-M稳定相关曲线，并提出了钢管约束型钢混凝土构件偏压承载力简化计算公式。更多还原

【Abstract】 A steel-tube-confined concrete column (STC) is a new type of composite column based on the concepts of concrete-filled-steel-tube columns and steel-reinforced concrete column. STCs have the advantages of high bearing capacity, good ductility, good fire resistance, and convenient construction. Research on STCs began in recent years in China, with the initial focus being only on short columns under concentric loading. Research on slender STCs under eccentric loading has not previously been carried out, despite this being the more common engineering application. This paper describes an experimental study and theoretical analysis conducted on the behavior of slender STCs under eccentric loading.An experimental study was conducted to investigate the behavior of circular tube-reinforced concrete columns (CTRC). Eight circular tube-reinforced concrete specimens were tested under concentric loading, and16circular tube-reinforced concrete specimens were tested under eccentric loading. The main experimental parameters examined were the slenderness ratios of the columns, the eccentricity of the loading, and the steel tube confinement mode. The failure modes of the columns were investigated. The load–displacement curves of the columns and the load–stress curves of the steel tubes were measured experimentally. A mechanical model for the behavior of a slender CTRC under eccentric loading was developed based on the test results. A three-dimensional (3D) finite element method (FEM) model was also developed using ABAQUS to analyze the behavior of a slender CTRC under eccentric loading.A second experimental study was conducted to investigate the behavior of square tube-reinforced concrete columns (STRC). Eight square tube-reinforced concrete specimens were tested under concentric loading, and16square tube-reinforced concrete specimens were tested under eccentric loading. The main experimental parameters examined were the slenderness ratios of the columns, the eccentricity of the loading, and the steel tube confinement mode. The failure modes of the columns were investigated. The load–displacement curves of the columns and the load–stress curves of the steel tubes were measured experimentally. A mechanical model for the behavior of a slender STRC under eccentric loading was developed based on the test results. A3D FEM model was also developed using ABAQUS to analyze the behavior of a slender STRC under eccentric loading.A third experimental study was conducted to investigate the behavior of circular tubed-steel concrete columns (CTSRC). Twelve short circular tubed-steel concrete column specimens and12slender circular tubed-steel concrete column specimens were tested. The main experimental parameters examined were the slenderness ratios of the columns, the eccentricity of the loading, the steel tube confinement mode, and whether or not a shear key was present. The failure modes of the columns were investigated. The load–displacement curves of the columns and the load–stress curves of the steel tubes were measured experimentally. A mechanical model for a slender CTSRC under eccentric loading was developed based on the test results. A3D FEM model was also developed using ABAQUS to analyze the behavior of a slender CTSRC under eccentric loading.A fourth experimental study was conducted to investigate the behavior of square tubed-steel concrete columns (STSRCs). Twelve short square tubed-steel concrete column specimens and12slender square tubed-steel concrete column specimens were tested. The main experimental parameters examined were the slenderness ratios of the columns, the eccentricity of the loading, the steel tube confinement mode, and whether or not a shear key was present. The failure modes of the columns were investigated. The load–displacement curves of the columns and the load–stress curves of the steel tubes were measured experimentally. A mechanical model for the behavior of a slender STSRC under eccentric loading was developed based on the test results. A3D FEM model was also developed using ABAQUS to analyze the behavior of a slender STSRC under eccentric loading.Based on Mander’s confined concrete model, the load–displacement curves were computed using the fiber method. The calculated results agreed well with the experimental data. The equivalent rectangular stress was obtained using this model. Based on the theory of energy, the confined concrete ultimate strain was obtained. A method for calculating the section bearing capacity of a tube-reinforced concrete column under eccentric loading can be established using the equivalent rectangular stress and the confined concrete ultimate strain. The buckling factor for a slender column was obtained using the tangent modulus method. The magnifying coefficient of eccentricity can be obtained based on reinforced concrete design principles. Using the buckling factor for a slender column and the magnifying coefficient of eccentricity, we can obtain the bearing capacity of the member.Based on the hypothesis about the plastic behavior of an entire section presented in the European standard Eurocode4, the load–moment (N–M) curve of a CTSRC (STSRC) can be determined using the fiber method. A simplified method for calculating the section bearing capacity was employed, based on the four key points of the N–M curve. The N–M curve of a CTSRC (STSRC) member can be determined using the reduction bending moment method. In the same way, a simplified method for calculating the member bearing capacity was employed, based on the four key points of the N–M curve of the member.更多还原