bimoment

The elastic stiffness matrix of this new model is 14×14.The effect of axial force, shearing force, biaxial bending moment and bimoment was involved in the geometrical stiffness matrix of element.

该模型的弹性刚度阵为14×14阵，几何刚度阵考虑了轴、剪、双向双效应。

A new point is put forward that transverse bimoment has different influence on the two kinds of cross section thin-walled beams, and on their St-Venant principle conditions. 2.

同时对外载等效经常出现的横向双这一进行研究，指出它在开口闭口薄壁梁约束扭转问题圣维南原理适用条件分别占有不同的地位。