Lamb波在起重机主梁等板结构的传播特性研究

Research on Propagation Characteristics of Lamb Waves in Plate Stru cture of Crane Girder

针对Lamb波在起重机主梁板状结构中的传播机理展开研究,基于全局传递矩阵法和子波展开法,建立各向同性材料的声波传播特性理论模型,获得了板状结构的Lamb波频散方程。以起重机主梁常采用的钢板为数值仿真对象,根据建立的频散方程,利用MATLAB编写计算程序进行数值仿真研究,获得理论频散曲线,并与其他计算软件获得的结果进行对比,两者具有很好的一致性,表明理论模型及计算程序正确可靠。该研究成果为Lamb波在起重机主梁板状结构的应用奠定了理论基础,也为起重机大型构件的大面积无损检测提供了新的思路。

Theoretical researches are carried out on the propagation mechanism of Lamb waves in plate structure of crane girder.Based on the Global Matrix method and the wavelet expansion method,a theoretical model of the propagation characteristics of acoustic wave in isotropic materials is established,and the dispersion equation of Lamb wave in plate Structure is obtained.The steel plate often used in the crane girder is taken as a numerical simulation object,and a calculation program is written in MATLAB to conduct a numerical simulation study according to the established dispersion equation.Then,the theoretical dispersion curve is obtained and compared with the results obtained by other calculation software.The results of the two methods are consistent,which proves that the theoretical model and the calculation program are accurate and reliable.This research results lay a theoretical foundation for the application of Lamb waves in the plate structure of crane girder and also provide a new method for the large-scale nondestructive testing of large components of the crane.