GFRP管混凝土组合结构压弯构件非线性全过程分析

NONLINEAR FULL-PROCEDURE ANALYSIS OF CONCRETE-FILLED GFRP TUBE COMPOSITE MEMBERS SUBJECTED TO COMBINATION OF BEND AND AXIAL COMPRESSION

本文应用细观力学、经典层板理论、平截面假定、FRP约束混凝土本构模型及数值积分对GFRP管混凝土组合结构压弯构件进行了非线性全过程分析。通过理论计算发现GFRP管混凝土组合结构能有效地提高构件的承载力,且构件具有良好的变形能力。FRP壳体参与承载且有效地约束混凝土的变形,显著提高核心混凝土强度和变形能力。文中讨论了轴压比、长细比、径厚比、混凝土强度等级、纵筋配筋率、铺层角变化对极限水平荷载和极限水平位移的影响,从而得到了一些有益的结论。

With the help of mlcro-mechanics, laminate theory, plane section assumption, constitutive model of FRP confined concrete and numerical integration, an nonlinear full-procedure analysis has been finished for concrete-filled GFRP tube composite members subjected to combination of bend and axial compression. Making use of the theoretical calculation, it has been found that the ultimate strength can be significantly improved and deformability is satisfied with concrete-filled GFRP tube composite members. Hence FRP jacket can not only carry the load but also confine the deformation of core concrete effectively. As a result, beth strength and deformability of core concrete increase apparently. The effects of some parameters, such as the ratio of axial force to compressive capacity, slenderness ratio, ratio of diameter to FRP thickness, the strength of concrete, ratio of reinforcement and change of fiber orientation, on the limit horizontal load and displacement are discussed in this paper. Some conclusions are obtained.