冷弯厚壁钢管截面不同部位材料特性分布模型

Distribution Patterns of Material Properties for Crosssection of Coldformed Thickwalled Steel Rectangular Tubes

摘要:

对取自30种不同截面、不同厚度、不同钢材型号、不同厂家生产的冷弯厚壁矩形和方形钢管的568个试件进行了材料性能试验研究.结果表明：焊缝部位的屈服强度和极限强度相对于邻边均有提高；角部屈服强度提高系数随型钢中心线长与弯角内径之比的增大而增大，而各参数对极限强度的影响较小；焊缝两邻边间的强度差异很小.基于研究结果，提出了冷弯矩形和方形钢管屈服强度、极限强度、强屈比和伸长率沿截面的分布模型.当相应冷弯型钢截面的梁、柱强度和稳定分析中需要考虑冷弯效应的影响时，可以应用此分布模型.

关键词:冷弯厚壁钢管; 材性试验; 屈服强度; 冷弯效应; 材料特性

Abstract:

Five hundred and sixty eight test coupons taken from thirty coldformed thickwalled steel square and rectangular tubes with different sizes of sections, thickness of plates, grades of steel and different manufacturers were tested to investigate the effects of coldforming process on the material properties of different parts of sections. The test results indicate that the coldforming effects have obvious influence on the strength and ductility of coldformed thickwalled sections. The difference of material properties between two adjacent plates connected to the plate containing weld can be ignored. The yield and tensile strength of weld portion and corner parts are enhanced compared with the adjacent plates. The yield strength enhancement factors of corner parts increase with the increase of the ratio of the length of centerline to the inside diameter of corners, but the enhancement factors for tensile strength are independent on the respective parameters. Based on the investigation, distribution patterns of yield strength, tensile strength, tensile to yield ratio and percentage elongation of coldformed thickwalled steel rectangular hollow sections were proposed, which can be used for strength and stability analysis of corresponding beams and columns, while the coldforming effects are to be taken into account.

Key words:coldformed thickwalled tubular; material test; yield strength; coldforming effect; material property