冷弯翼缘闭合新型截面受弯构件性能研究

BEHAVIOR RESEARCH OF TWO NEW KINDS OF COLD-FORMED FLANGE-CLOSED SECTION BEND MEMBERS

空翼缘梁(Hollow Flange Beam——HFB)具有截面形式开展,抗弯、扭刚度大的特点,主要用于承受弯矩。借鉴HFB的截面形式,适当改变其截面构成及截面参数,提出两种新型冷弯翼缘点焊闭合截面——HF1和HF2。采用有限元方法,建立适于冷弯截面受弯构件性能分析的非线性有限元分析模型。模型中考虑各种影响构件承载力的因素,包括材料的强化、局部屈曲、构件失稳以及构件的初始几何缺陷。通过对新型截面的变形模式、跨中相对挠度、弯矩-曲率曲线、极限弯矩等方面的研究,全面分析两种截面构件的静力性能。分析表明,新型截面构件具有刚度大、抗弯承载力高、截面局部屈曲不易发生等优越的受力性能,可以深入试验研究并合理推广使用。

Hollow flange beam （HFB） has particular cross section with two torsionally rigid closed triangular flanges and a comparatively flexible web, it is a type of high efficient cross section mainly used as flexural members. Based on the HFB section, it is put forward that two new kinds of cold-formed flange-closed welding sections named HF1 and HF2 through changing the component of section and section parameters of HFB. It is also presented a finite element analytical model suitable for non-linear analysis of HFB flexural members. The model includes all significant effects that may influence the ultimate capacity of such members, including material inelasticity, local buckling, member instability, web distortion, and geometric imperfections. On the base of precise finite element model, nonlinear finite element method is adopted to study the new sections＇ buckling modes, relative deflection, moment-curvature curves, and ultimate capacity. The static behaviors of the two kinds of sections are analyzed completely. It can be concluded that the new sections have the well characteristic of high rigidity, high ultimate capacity, local buckling of the sections always hard to occur, and can go deep into the experiment study as to be used in the practical engineering.