【摘要】 T型焊接接头是海洋工程中较为典型的结构细节 ,研究其低温P—da dN—ΔK曲线 ,对确定焊接构件在冬季服役时的检修周期具有重要意义。在 10 0吨MTS电液伺服材料试验机上进行了 3件T型焊接接头的低温疲劳裂纹扩展试验 ,测出了其中值da dN—ΔK曲线。通过小样本试验的理论推导与计算 ,利用变异系数CV 的经验取值 ,初步得出T型焊接接头的低温P—da dN—ΔK曲线更多还原

【Abstract】 T welded joint is the typical details of offshore engineering structure. The study on the P —d a /d N —Δ K curve at low temperature is very important in determining the examination period of welded components in winter. The fatigue crack propagation experiment of three type T welded joints at -25℃ was carried out on 100 t MTS testing machine, and the d a /d N —Δ K curve have been derived. By the theoretical analysis and practical calculation of small sample experiments assuming the experiential C V value of lg(d a /d N ) is constant at the crack propagation stage, the P —d a /d N —Δ K curve at low temperature of type T welded joints is preliminarily obtained.更多还原