As increasing external loads, from part yield to plastic expanding, stress is dstributed again, at last two models are yielded axisymmetrically, there is no buckling characteristic.

• 随着静水外压的增加，模型结构从局部屈服到塑性区扩展，应力重新分布，直至发生轴对称屈服破坏，未见失稳特征。