In this paper, a new interpretation and modification of the SWT function in terms of the total damaging energy density are proposed and discussed. The total damaging energy density is the sum of the damaging part of the strain energy density and complementary energy density corresponding to the first quadrant in damaging σ_D-ε_D axes. For cyclic loading with a positive mean stress (σ_m ≥ 0), the proposed function reduces to the original SWT formulation. For cyclic loading with a negative mean stress (σ_m < 0), the maximum stress is augmented by 1/3 of absolute value of the mean stress. The proposed approach shows a consistent correlation of the mean stress effects for both positive and negative mean stresses.

中文翻译：

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SWT函数的解释和修改

在本文中，提出并讨论了根据总破坏能量密度对 SWT 函数的新解释和修改。总破坏能量密度是破坏σ _D -ε _D轴的第一象限对应的应变能量密度和互补能量密度的破坏部分之和。对于具有正平均应力 ( σ _m  ≥ 0) 的循环载荷，建议的函数简化为原始 SWT 公式。对于具有负平均应力 ( σ _m  < 0) 的循环载荷，最大应力增加了平均应力绝对值的 1/3。所提出的方法显示了正负平均应力的平均应力效应的一致相关性。