闭口薄壁杆件的约束扭转剪应力分析

Study on the Shear Stress of Thin-walled Member with Closed Section under Restrained Torsion

基于周边不变形理论,推导了闭口薄壁杆件的约束扭转剪应力计算公式,对有关文献中的另一种剪应力公式进行了分析与论证,发现这些文献中对闭口薄壁杆件约束扭转时的纯扭转剪应力和约束扭转剪应力的表达是不正确的,并进行了更正.最后通过一个发生约束扭转的悬臂箱梁算例,具体分析比较了按本文公式和有关文献中公式计算的约束扭转剪应力的差别.

On the basis of the rigid perimeter assumption, the shear stress formula for the thin-walled member with closed section under restrained torsion is derived. The other type of shear stress formula in relevant references is studied and demonstrated. The wrong expressions about the shear stresses corresponding to pure and restrained torsion are found in these references for the thin-walled member with closed section under restrained torsion. The error is corrected through a systematic demonstration. At last, a cantilever box girder under restrained torsion is analyzed as an example. The restrained torsion shear stresses calculated by the present and the other formulas are compared. The present work perfects the theoretical analysis of thin-walled member with closed section to certain extent.