矩形薄壁管在空间内力作用下的强度分析

On intensity analysis of rectangle thin wailed tube under space endogenetic process

现代建筑或桥梁工程中薄壁型材应用较广,一般在杆件结构设计上尽量为平面受力状态,但因特殊工况要求某些杆件所受外力较复杂,是在空间内力系(6个内力分量)作用下工作。为了确保杆件工作安全可靠,必须对其强度进行分析。以常见的矩形薄壁管构件为例研究,理论分析表明其强度破坏必在外表层处,即最大应力点一定在薄壁管表面某些点上。利用材料力学方法分析解决杆件横截面上存在多个内力的强度计算问题,进而确定危险点的位置。

The thin wailed section bar is used widely in modern construction and bridgework, so the plane stress model is applied mostly in rod piece structure design. However, due to special working conditions, the external force of some rod pieces is complex. It is working on the condition of space inner force system （6 in- ner force components）. For the purpose of ensuring the safety and reliability of rod pieces, the intensity analy- sis must be done. Taking usual rectangle thin wailed tube for example, theoretical analysis shows that the in- tense destroy must happen on the surface part, that is, the maximum stress point must stay at some part of thin wailed tub surface. According to shear stress equal theorem, the shear stress is sure to be zero at every spot like a, b, e, d （refer to chart-l（b） ）on the cross section edge, and the unit is under one-way stress state, but each spot like e,f,g,h（refer to chart- 1 （b）） is under plane complex stress state. Supposing the material researched is linear and flexible, the calculation of intensity of multi - inner force spots existing on rod piece cross section can be solved well through the way of mechanics of materials.