基于区间因子法的龙门起重机主梁动力学响应分析

Dynamic response analysis of girder of gantry crane based on interval factor method

工程机械中研究结构的固有特性、静力学和动力学响应通常基于确定性的参数,但在现实生活中,由于加工和测量误差等因素,使得材料属性、外载荷、初始条件和结构参数等存在误差和不确定性,故不确定性参数对工程结构影响具有非常重要的意义。文中将求解简单且应用广泛的移动载荷模型应用于简支梁中,从而得出运动微分方程,并利用振型叠加的原理求解出模态坐标的相关表达式,再结合区间因子法和简支梁的3种不确定模型,得出结构动力响应区间变量的区间分散性与结构几何参数、运动参数、物理参数和外载荷区间分散性之间的关系,最后将理论结果应用到龙门起重机主梁分析中,从而得出不确定性参数对龙门起重机主梁结构动力学响应的影响。

Researches on inherent characteristics,statics and dynamic response of construction machinery structures are usually based on deterministic parameters.However,factors such as processing and measurement errors will cause errors and uncertainties in material properties,external loads,initial conditions and structural parameters,so the influence of uncertain parameters on engineering structures is of great significance.The moving load model,which is simple and widely used,is applied to the simply supported beam to obtain the motion differential equation,and the related expressions of modal coordinates are obtained according to the principle of mode superposition.Combined with the interval factor method and three uncertain models of the simply supported beam,the relationship between the interval dispersion of structural dynamic response variables and the interval dispersion of structural geometric parameters,motion parameters,physical parameters and external loads is obtained.Finally,the theoretical results are applied to the analysis of gantry crane girder,so as to find out the influence of uncertain parameters on the dynamic response of gantry crane girder structure.