冷弯厚壁型钢钢管冷作硬化效应

通过对冷弯厚壁钢管上截取的平板板材、弯角板材、母材和相应方、矩形截面短柱的试验研究，得到短柱全截面屈服强度相对于母材强度的提高值．运用国内外相关规范的计算公式对短柱屈服强度实测值进行对比分析，表明这些公式都不宜直接用于我国冷弯厚壁型钢的屈服强度计算．根据试验结果，在《冷弯薄壁型钢结构技术规范》（GB50018-2002）基础上，提出适用于冷弯厚壁型钢的计算公式，将修正公式计算结果与试验实测数据对比，证实了该公式有效．

Strain Hardening of Thick-Walled Cold Formed Steel Tube

Through experiments on the plates, corner plates, base metal plates and corresponding square or rectangular stub columns cut from thick-walled cold formed steel tubes, the increase values of yield strengths of the whole cross section of stub columns caused by strain hardening were acquired. Then equations of correlative codes in China and abroad were used to analysis the test data. The results show that all of them are not fit for thick-walled cold formed steel tubes in China. Based on the test data and GB50018-2002, a modified equation was put forward, by which yield strengths of thick-walled cold formed steel tubes in the experiment were calculated, and they were compared with the test data, showing that this equation is valid.