【摘要】 采用高阶有限梁单元,研究梁或刚架结构附带集中质量的固有频率及其灵敏度计算问题。通过在节点上增加曲率和曲率的一阶导数两个独立的自由度,可以直接获得频率灵敏度计算所需的基本量。计算结果表明:用高阶梁单元,可以较精确地获得固有频率及其对集中质量位置的灵敏度值。此外,经过比较发现,在单元网格划分比较密集的情形下,采用通常的2节点4自由度梁单元,也能获得比较满意的频率灵敏度计算结果。更多还原

【Abstract】 The calculation of dynamic behaviors of a beam structure with a lumped mass with both translational and rotary inertias was studied using two types of higher-order beam elements.By adding respectively independent variables of the curvature and its first-order derivative at a node,the frequency and its sensitivity with respect to the position of the lumped mass attached were calculated accurately using the higher-order beam elements.Numerical results show that the use of generic beam element of the cubic polynomial displacement can also achieve the frequency sensitivity satisfactorily with a dense finite element mesh.更多还原