【作者】 顾威；

【导师】 赵颖华；

【作者基本信息】 大连海事大学 ， 道路与铁道工程， 2007， 博士

【摘要】 本文针对钢管混凝土构件和CFRP钢筋混凝土构件在工程实践中存在的具体问题，提出新的结构形式CFRP-钢管混凝土结构。该结构避免了大型钢管混凝土构件必须采用厚壁钢管或高强钢管的造价较高的问题，降低耗钢量、减轻构件自重，或避免大量高强钢的消耗，在一定程度上解决钢管的腐蚀问题；又可以解决FRP筒塑性较差的问题。该构件为几种材料的组合结构，力学性能复杂，本课题通过理论和实验研究，探讨了这种新型结构的力学行为，建立了基本设计计算方法，为解决工程设计和应用提供科学依据。 对CFRP钢管混凝土构件的力学性能进行理论分析，从轴压短柱构件，偏压构件和轴压长柱构件三个方面来进行论述。 在实验研究的基础上，对CFRP钢管混凝土轴压短柱应用两种方法分析其极限承载力，极限平衡法和弹塑性力学方法。试验和理论研究的结果表明，CFRP可以有效的提高钢管混凝土轴压短柱构件的极限承载力。为评价CFRP的增强效果，将钢管混凝土的约束效应系数的概念引入到这种新型构件中，为该种新型构件的偏压构件的力学性能研究提供了理论依据。 给出偏压短柱的极限承载力的计算公式，与试验结果吻合良好。同时在钢管混凝土安全系数法的基础上，修正了长细比折减系数和偏心率折减系数，提出了CFRP钢管混凝土构件折减系数法确定构件偏压柱的临界承载力，为该种新型构件的偏压柱设计计算提供了有效的方法。 通过对CFRP钢管混凝土轴压长柱的试验研究，了解其工作机理。在此基础上，分别应用欧拉公式和长细比折减系数法给出了CFRP钢管混凝土轴压长柱的临界承载力计算公式，与试验得到的结果比较吻合良好。 为了弥补实验数量不足的缺憾，对CFRP钢管混凝土轴压短柱进行了有限元分析，模拟了构件荷载-变形全过程曲线。在有限元分析中，考虑材料的非线性于各向同性，运用并修正了钢管混凝土结构中混凝土的本构关系。更多还原

【Abstract】 The aim of this paper is to introduce this structure in three aspects: accomplished work, the mechanics of short columns and long columns.In the first part the background and the states of study on the CFCST(concrete filled CFRP steel tube) are introduced simply; there are experiment and theoretical analysis on the mechanics of the CFCST columns under axial compression in the chapter two.In the second part the mechanics of the short CFCST columns is investigated: Firstly the ultimate strength of CFCST is obtained after the steel tube is plastic with the theory of Hencky’s plasticity. The equation is derived for estimating the strengths of the system in the case CFRP-sheet break; At the same time the hoop force between steel tube and concrete is ascertained. The concept of the equivalent hoop force is cited with the effect of slenderness and eccentricity ratio. On the basis of these theories the balanceable equations between forces and moment deduced stabilized load capacity; the eccentricity ratio coefficient and slendemess ratio coefficient are put forwards and the safe coefficient on the CFST is revised to deduce load capacity of the CFCST.In the numerical simulation based on the constitutive relations of concrete and steel tube of the CFST the constitutive relations of the CFRP, steel and concrete are put forwards. The short CFCST columns under axial loading are analyzed by using finite element software ANSYS and their loading-strain curves are obtained. These curves agree with experimental curves.In the third part the theoretical and experimental analysis on the long CFCST columns are investigated. The relation and difference between short CFCST column and short CFST column are studied through these two structures experiment, and the experiment of long CFCST column under axial compression were carried on; On these basis mechanical properties and the increment ratio of load bearing capacity of the concentrically compressed the CFST columns due to CFRP are studied; The influence of slenderness ratio on the load bearing capacity of the specimens is analyzed; The equation is derived for estimating the stability strengths of the system and the calculated results accorded with the text results .更多还原