模数式桥梁伸缩缝固有频率及结构参数灵敏度分析

Analysis of Natural Frequency and Structural Parameter Sensitivity of MBEJs

为更全面地了解模数式桥梁伸缩缝动态响应,以ZL480模数式桥梁伸缩缝为研究对象,应用ANSYS软件建立其参数化模型,分析改变横梁间距BHK、中梁支撑刚度K2和缝宽B等参数对其固有频率和灵敏度的影响。研究结果表明:当横梁间距BHK从1 m增加到2 m,间距增加100%,第1阶固有频率ω1减小了32.6%;中梁支撑刚度K2从40 000 N/mm增加到100 000 N/mm,刚度增加了150%,第1阶固有频率ω1增加了24%;随横梁间距BHK的减小、横梁下支撑刚度K4、中梁支撑刚度K2、中梁刚度K1的增大,模数式桥梁伸缩缝固有频率逐渐增大,且灵敏度依次降低;缝宽B及横梁刚度K3的改变对其固有频率影响不大。

For more comprehensive understanding the dynamic response of MBEJs, taking ZL480 as the research object, the MBEJ model is established by using ANSYS software. The structural parameters of MBEJs, such as cross beam span BHK, centre beam support stiffness K： and lamella span B, which impact the natural frequency and sensitivity are studied. The result shows that （1） when the cross beam span BHK increases from 1 m to 2 m, the first-order natural frequency ω1 is reduced by 32.6% , while the centre beam support stiffness K2 ranges from 40 000 N/mm to 100 000 N/mm and it is increased by 150% , the first-order natural frequency ω1 is increased by 24% , （2） the natural frequency of MBEJ increases gradually and its sensitivity decreases in order as cross beam span decreases and cross beam support stiffness/（4, centre beam support stiffness K2, and centre beam stiffness K1 increase; （3） the changes of lamella span B and cross beam stiffness K3 has little effect on its natural frequency.