矩形钢管混凝土-波纹腹板组合梁局部受压承载力研究

Load carrying capacity of locally compressed I-girders with rectangular concrete-filled tubular flange and corrugated web

利用数值模拟方法对矩形钢管混凝土-波纹腹板组合梁(RCFTFG-CW)的局部承压承载力进行研究。建立了在集中荷载作用下RCFTFG-CW与波纹腹板工字形梁(IG-CW)腹板发生局部承压破坏的有限元分析模型。通过与相关文献结果对比,验证了有限元模型的可靠性。利用验证后的有限元模型研究了RCFTFG-CW的局部承压承载力、应力发展过程以及荷载作用位置对承载力的影响。分析了几何尺寸、材料特性、荷载作用长度(沿梁跨度方向)以及波纹展开长度和波长的比值对RCFTFG-CW局部承压承载力的影响。在参数分析的基础上,提出了RCFTFG-CW的局部承压承载力的设计表达式,并利用有限元分析结果验证了公式的准确性。结果表明,与IG-CW相比,RCFTFG-CW具有更高的局部承压承载力;RCFTFG-CW的局部承压承载力分别与钢管混凝土上翼缘等效惯性矩的1/4次方、腹板厚度、波纹展开长度与波长的比值、荷载作用长度呈线性增长关系;所提出的计算公式能够精确预测RCFTFG-CW的局部承压承载力。

The load carrying capacity of locally compressed I-girders with rectangular concrete-filled tubular flange and corrugated web(RCFTFG-CW) is investigated through numerical simulation method. Finite element(FE) models of steel I-girders with rectangular concrete-filled tubular flanges and corrugated web and corresponding I-girders with flat-plate flanges and corrugated web(IG-CW) under concentrated load at mid-span are built. The reliability of the presented FE models is verified through comparing the FE results with reported experimental results. Through FE analyses by using the FE models, local compressive strength, stress development, and effect of loading location on the strength are analyzed and compared. The influences of variation of geometric parameters, material properties, load distribution length(along the span of girder) and the ratio of the stretched length of the wave to the wave length on the local compressive strength are further investigated. Based on parameters analysis, formula for calculating the local compressive strength of RCFTFG-CW are proposed, and the accuracy of the formula is verified by the results of finite element analyses. The results indicate that RCFTFG-CW has a higher local compressive strength compared to that of IG-CW. The local compressive bearing capacity increases proportionally to the equivalent moment of inertial of the concrete-filled tubular flange to the 1/4 power, the thickness of the web, the ratio of the stretched length of the wave to the wave length and loading length. The presented formula are proved to be accurate to predict the local compressive strength of RCFTFG-CW.