门式启闭机有效悬臂端挠度计算公式探讨

Discussion on the calculation formula of deflection at effective cantilever end of gantry crane

以1250 kN门式启闭机为例,采用《起重机设计手册》中挠度理论计算公式与有限元软件分别对有效悬臂端挠度进行了计算,结果显示理论公式挠度值比有限元软件所得挠度值小。通过推导,发现理论公式没有考虑剪切与拉伸变形引起的位移,采用推导所得公式计算得到的结果与有限元计算结果无限接近,说明推导的公式具有较好的实用性。

Taking 1 250 kN gantry crane as an example,this paper calculates the deflection at effective cantilever end using two methods,one is the theoretical calculation formula of defection in Crane Design Manual,and the other is finite element software.The result shows that the theoretical deflection value is smaller than the value obtained by finite element software.By derivation,it is found that displacements of shear deformation and tensile deformation are not considered in the theoretical calculation formula.After that,this paper calculates the defection using the derived formula and its result is incredibly close to that of finite element calculation,which shows that the derived formula has great practicality.