结合塑性力学理论和模态综合技术，提出一种快速分析柔性结构在冲击载荷下的弹塑性瞬态响应的求解方法。该方法基于“伪力”思想，通过引入预测参数将弹塑性变形导致的非线性特征近似等效为一具有力量纲的外载荷，并置于控制方程右边保持方程左边线性，而后采用模态综合技术建立原系统的降阶模型，并给出相关方程的求解方法。经此变换后，用于建立降阶模型的模态变换矩阵只需计算一次，且在整个响应计算过程中保持不变，有效地提高了计算效率。通过计算柔性简支梁在谐振载荷和碰撞载荷下的弹塑性响应，并与全模型的计算结果对比，验证了该方法求解柔性结构弹塑性瞬态响应的准确性和高效性。
A numerical method is presented to incorporate plastic mechanics theory with component mode synthesis technique for the analysis of elastic-plastic dynamic responses of flexible structure subjected impulsive load. To do this, the nonlinearity induced by plastic deformation is treated and approximated as an internal excited load, which is placed on the right-hand side of the incremental governing equations. This technique is so-called pseudo-force method. And then, the governing equations of plastic dynamic problems in modal coordinate are derived from fixed-interface component mode synthesis technique, the solving method of these equations is also introduced. By using the proposed method, the modal transformation matrix of system is calculated only once, and is used throughout the entire analysis. This will be an improvement of computational efficiency. A simply supported beam suffered harmonic load and impact event are studied, respectively. The simulation results show that the proposed method has a higher computational efficiency and accuracy by comparing with the full model finite element method.
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