Research on buckling collapse behavior and ultimate strength of stiffened plating in compression

在本研究项目中研究的研究问题的项目和结果如下。（1）加筋板在轴向力作用下的破坏分析中对加筋板建模的考虑通过对加筋板的破坏分析，发现用板来模拟腹板、用梁柱来模拟翼缘是最有效的建模方法。（2）加劲肋相对于板的倾斜角对加筋板屈曲破坏行为的影响研究发现，倾斜角对加筋板的局部屈曲强度没有影响，但对极限强度以上的承载力和整体屈曲强度有影响。（3）ISUM在组合荷载作用下加筋板破坏分析中的应用将新型ISUM板单元与梁柱单元相结合，可以较准确地模拟双向压载作用下连续加筋板的破坏行为。（4）加筋曲板的屈曲/塑性失稳研究发现，加筋曲板的弹性局部屈曲强度与其塑性失稳强度有关， 关于我们 GTH随着弯曲角度的增加而线性增加。另一方面，实际船舶结构中的曲板发生塑性屈曲，其极限抗压强度与屈服强度接近。（5）残余应力对加筋板屈曲破坏行为的影响轧制和焊接T型加筋板腹板和翼缘残余应力的符号。但这种差异对加筋板的极限抗压强度影响不大。（6）考虑加劲肋脱空对加筋板破坏行为的影响研究发现，由于整体弯曲，在受压侧加劲肋腹板处发生脱空。跳闸发生的条件尚不清楚。（7）铝合金加筋板的屈曲、屈曲性能和强度采用焊接连接轧制加筋板时，焊接残余应力提高了铝合金加筋板的屈曲和极限强度。另一方面，热影响区材料的软化降低了铝合金加筋板的极限抗压强度。少

The items and results of research issues which have been studied in the present research project are as follows.(1)Consideration on modelling of stiffeners in the collapse analysis of stiffened panel under axial thrustIt was found that most effective modeling is to model the web by plate and the flange by beam-column.(2)Influence of inclination angle of stiffeners to plating on buckling collapse behavior of stiffened platesIt was found that inclination angle does not affect the local buckling strength, whereas it affects the capacity beyond the ultimate strength as well as the overall buckling strength.(3)Application of ISUM to collapse analysis of stiffened plates subjected to combined loadingCombining new ISUM plate element and beam-column element, collapse behavior of continuous stiffened plates under combined bi-axial and pressure loading was simulated very accurately.(4)Buckling/plastic collapse behavior of curved stiffened platesIt has been found that elastic local buckling stren … More gth increases linearly with the increase in curved angle. On the other hand, the curved plates in actual ship structure undergoes plastc buckling, and the ultimate compressive strength is nearly equal to the yielding strength.(5)Influence of residual stress in stiffeners on buckling collapse behavior of stiffened platesThe sign of the residual stress in web and flange opposite in rolled and welded T-type stiffeners. However, this difference affect a little on the ultimate compressive strength of stiffened plate.(6)Consideration on influence of stiffener tripping on collapse behavior of stiffened platesIt was found that tripping takes place at the stiffener web in the compression side of bending resulting from over-all bending. The condition for the occerrence of tripping is left unknown.(7)Buckling collaose behavior and strength of alminium stiffened platesThe welding residual stress increases the buckling/ultimate strength of alminium stiffened plate when the stiffened plate is fabricated by connecting rolled stiffened plates by butt-welding. On the other hand, softening of the material in heat affected zone reduce the ultimate compressive strength of alminium stiffened plates. Less