论文部分内容阅读
利用虚功法,并不考虑纯弯曲型杆件的剪切影响,求出烟囱各分段质量处的位移。再利用柔度矩阵列出多自由度体系的自由振动方程[u] {A~(r)}=入{A~(r+1},式中[u]为质量柔度矩阵,仅与质量分布及刚度有关。按照所要求的精度反复迭代,并利用振型正交性,求得第一、二、三振型的频率ω_j及周期T_j。最后按振型组合求出各截面的内力。
By using the virtual work method, the shear effect of the purely curved member is not considered, and the displacement at the mass of each segment of the chimney is found. Then use the flexibility matrix to list the free vibration equation of the multi-degree-of-freedom system [u] {A~(r)}=in {A~(r+1), where [u] is the quality flexibility matrix, only with the quality It is related to the distribution and stiffness, iteratively repeats the required accuracy, and uses the orthogonality of the mode shape to obtain the first, second, and third mode frequencies ω_j and T_j.Finally, the internal forces of each section are obtained by the mode combination.