论文部分内容阅读
薄壁箱形梁具有重量轻,抗扭性好等显著特点,近年来已被日益广泛地应用在起重机的金属结构主梁上。这种结构的计算与材料力学里的初等弯曲理论有所不同。在初等弯曲理论里,假设在横剖面内,纵向纤维的相对变形是按平面规律分布的。即弯曲时正应力按平面分布,横剖面能自由翘曲。但在实际上,在横向弯曲作用下,由于剪应力将使剖面产生翘曲,
Thin-walled box girder with light weight, good torsion resistance and other notable features, in recent years has been increasingly widely used in crane girder metal structure. The calculation of this structure is somewhat different from the elementary bending theory in material mechanics. In the elementary bending theory, it is assumed that in the cross section the relative deformations of the longitudinal fibers are distributed in a plane law. That is, when bending is distributed according to the plane stress, cross-section can freely warp. However, in fact, due to lateral bending, the shear stress will make the profile warp,