基于梁壳复合有限条法的矩形渡槽自振特性分析

Free Vibration Analysis of Rectangle Aqueducts Based on Beam-shell Compound Finite Stip Method

根据具有多片侧墙的矩形渡槽横截面形状规则的特征,采用弯曲和平面组合有限壳条离散渡槽槽身,利用空间梁单元模拟加劲构件,将壳条及壳条内的空间梁单元耦合组合成梁壳复合有限条,根据Hamilton变分原理,建立具有多片侧墙的矩形渡槽的梁壳复合有限条计算模型,推导得出梁壳复合有限条元的刚度矩阵和质量矩阵,进行矩形双槽渡槽自振特性分析。计算结果表明:梁壳复合有限条法在分析横截面形状规则的渡槽结构时,单元划分简单,数据输入少,具有良好的求解精度和效率;具有多片侧墙的矩形渡槽的振型复杂,槽身设计参数的变化会改变振型序列的顺序。

According to the regularity of multi-side wall rectangle aquedcuts＇ cross-section,the beam-shell compound finite strip method is presented.Finite shell strip combined by bending strip and plane strip is used to discretize aqueducts＇ body,and spatial beam element is used to discretize the transverse stiffeners.The stiffness matrix and mass matrix are obtained by Hamilton＇s principle.Numerical example is given to show the exactness,efficiency and applicability of the proposed method for aqueducts.The research results show that the vibration mode of aqueducts is complex,and the design parameters influence the sequence of the vibration mode.