Q235B直缝焊管轴向冲击性能的理论和试验研究

Theoretical and experimental studies on the axial impact behavior of Q235B longitudinally welded tubes

基于Alexander静态压溃模型和Cowper-Symonds经验方程,推导出含应变率效应的圆管动态平均压溃力预测公式,同时论述了它与Abramowicz提出的理论公式异同点。然后利用跌落塔装置对9种规格的Q235B直缝薄壁焊管进行冲击试验,将理论预测值与实测值进行对比,结果表明:基于Alexander模型推导出的动态平均压溃力预测值整体偏小,而Abramowicz公式的预测值整体偏大。最后结合冲击试验过程和结果,修正了Abromowicz的平均压溃力预测公式,将应变率敏感系数3.91调为3.0,修正值与所有试验值吻合良好,最大偏差不超过8%;另外,还给出了用于预测中等尺寸薄壁焊管的简易动态峰值压溃力预测公式。

Based on the Alexanders theoretical crushing model and the empirical Cowper-Symonds equation, a formula including strain rate effect for predicting dynamic mean crushing force of circular tube was derived. And its derivation differences from the theoretical formulas put forward by Abramowicz were discussed. Then it adopted the drop tower rig to make the impact test for 9 kinds of Q235B longitudinally thin-walled welded tubes, and the test results were compared with theoretical prediction values. The result comparison shows that the predicting formula of dynamic mean crushing force derived from the Alexander’s model gives lower values,and Abramowicz’s formulas give higher values. At last, referring to impact test conditions and results, it modifies the Abramowicz＇s formula by setting sensitivity coefficient of strain rate from 3.91 to 3.0. The modified values correlate well with all test results and the maximum deviation is lower than 8% . In addition, it also proposes a simple dynamic peak crushing force formula for predicting thin-walled welded tubes with media sizes theoretically.