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当前轮式起重机向着起重量大、机动性好、重量轻的方向发展。要求臂架重量轻、刚度强、稳定性好,因而研究比较精确的计算方法是非常必要的。加权余量法是可以直接从微分方程式中得到近似解的一种数学方法,用这种方法计算箱形伸缩臂比用有限单元法具有单元少、公式简单、计算量小等优点。考虑到箱形伸缩臂是一个变截面压弯构件,主要是刚度和稳定问题,它的计算特点是必须考虑轴向力对弯曲变形和弯矩的影响。本文提出了在计算变形时用引入弯矩扩大系数的方法来考虑轴向力对弯矩的影响,并用加权余量法推导了臂架的变形扩大系数,弯矩扩大系数,变形计算公式及应力计算公式,还排出了电算程序。该程序不仅可用以
The current wheeled cranes are developing in the direction of heavy weight, good maneuverability and light weight. The boom is required to be lightweight, rigid, and stable. Therefore, it is very necessary to study a relatively accurate calculation method. The weighted residual method is a mathematical method that can obtain approximate solutions directly from differential equations. Using this method to calculate the box-shaped telescopic boom has fewer advantages such as fewer units, simple formula, and less computational complexity than using the finite element method. Considering that the box-shaped telescopic arm is a variable-section bending and bending member, it is mainly a problem of stiffness and stability, and its calculation feature must consider the influence of the axial force on bending deformation and bending moment. In this paper, the influence of the axial force on the bending moment is considered when calculating the deformation with the method of introducing the bending moment expansion coefficient, and the deformation expansion coefficient, bending moment expansion factor, deformation calculation formula and stress of the boom are deduced by the weighted residual method. The calculation formula also discharges the computer program. This program can not only be used