一种超级梁单元桁架式臂架结构强度荷载计算

The calculation of the strength bearing capacity of the lattice boom structure is one of the central calculations of the boom crane. A single boom section is considered as a substructure to condense its internal degrees of freedom to the left and right ends. Based on the assumption of the rigidity of the ends of the boom section, the boundary degrees of freedom are further condensed to the centroid of the boom section's ends, and the weight of the boom section is discretized to the centroid node to form a super beam element considering the gravity. Based on the co-rotational coordinate method, the floating coordinate system of each boom section is established, which can accurately calculate the element stress taking into account the geometric nonlinear effect of long boom. By establishing the balance equation of the node force of the boom, the displacement and rotation angle of the beam element nodes are obtained, and the structural strength of the boom is calculated. Based on the numerical interpolation method, a fast search method of strength load is proposed to realize the fast search of boom strength load and obtain the bearing capacity of boom strength. The numerical examples show that this method has high efficiency and accuracy in the fast calculation of the strength bearing capacity of lattice boom structure.