残余应力的筛降效应及其对矩形板强度的影响

摘要

分析了船体板中残余应力的筛降,得到了在受拉和受压情况下的筛降水平的计算公式,并用有限元程序模拟了残余应力的筛降过程,验证了公式的有效性.分析了残余应力的筛降对板的平均应力-平均应变曲线的影响,采用两种方法分别得到了考虑筛降效应的板的平均应力-平均应变曲线的表达式,用有限元法进行了模拟计算,结果表明,分别计算受残余拉应力和残余压应力区的应力得到的平均应力-平均应变曲线和有限元计算结果符合得更好.%The shake down effect of residual stress in the rectangular plates in stiffened panels is studied and the formula to calculate the level of the shake down effect is developed.The process of shake down is simulated with FEM program and the formula is validated by the FEM results.The influence of the shake down effect on the curve of average stress-average strain is studied.With two different methods, the formula for average stress-average strain curve of plates with the shake down of residual stress is deduced. The curve is also generated with FEM. Comparison to the result of FEM shows that the method considering the two parts of residual tensile stress and residual compressive stress respectively has the better result.