为了扩展谱元法的适应性，针对承受冲击载荷的结构动态响应问题，从谱单元离散方案出发并根据冲击载荷的特点，以冲击载荷最大值点为中心将谱单元尺寸按一定比例等比向两侧扩大，实现单元尺寸与载荷特征相适应，在此基础上，将动力学方程转化为1阶线性微分方程组，通过Bubnov-Galerkin法获得离散线性方程组，应用高斯消元法求解。最后，应用此方法对标准形式、线性单自由度吸振器、124杆桁架结构和连杆小头问题进行计算并与等距谱元法进行比较，说明了此方法的可行性和有效性。%The spectral element method (SEM) is used to analyze the dynamic responses of the structures subjected to impact loading. Starting with the SEM discrete scheme and according to the feature of the impact loads, each spectral element is enlarged proportionally from the middle point of the impact load to both sides of the element to realize the suitability between the element size and the loading feature. On this basis, the dynamic equation is transformed to a set of the first-order linear differential equations, and the corresponding discrete linear algebraic equations are obtained by Bubnov-Galerkin method and solved by Gauss elimination method. Finally, four examples of a typical absorber, a linear single DOF absorber, a 124-member plane truss and the small end of a link are calculated with this method and the results are compared with those of the equal-spaced SEM. The feasibility and validity of this method are verified.
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