加筋板固有频率与相对刚度对其非线性动力响应的影响

Impacts of natural frequency and relative stiffness of stiffened plate on nonlinear dynamic response

[目的]研究冲击载荷对船用加筋板动力响应的影响。[方法]首先,根据相关规范和参考文献确定船用加筋板的尺寸,并运用有限元软件ANSYS中的Shell 181单元进行建模;然后,将载荷均匀作用于带板表面,加筋板的边界条件为四边固支;最后,分析在冲击载荷作用下加筋板的固有频率和相对刚度对其非线性动力响应的影响。[结果]结果显示,由几何尺寸影响的不同,可得到固有频率与挠度响应的分段函数关系式;加筋板的相对刚度则对其变形模式影响较大,以0.2和19为界,出现了不同的变形模式。[结论]所得定量化结论对船体结构安全评估具有重要的参考价值。

[Objectives]This paper studies the influence of impact load on the dynamic response of marine stiffened plates.[Methods]According to the relevant specifications and references,the sizes of hull stiffened plates are determined.Finite element software ANSYS is used for modeling with Shell 181 element.The load is applied uniformly on the surface of the stiffened plate,and its boundary condition is fixed.The impacts of the natural frequency and relative stiffness of the stiffened plate on its nonlinear dynamic response under impact load are then analyzed.[Results]The results show that the piecewise function relations expression of natural frequency and deflection response are obtained according to the different influences of geometric dimensions.The relative stiffness of the stiffened plate affects its deformation mode,and the critical values are 0.2 and 19.[Conclusions]These quantitative conclusions have important reference value for the safety evaluation of hull structures.