结构中不平衡弯矩产生的内力问题分析研究

Analysis and Research on internal force caused by unbalanced moment in structure

所有结构内力、外力(轴力、剪力、弯矩和扭矩)都应平衡,否则结构就会破坏、倒塌。结构中不平衡弯矩有两种情况:(1)结构截面不匹配,结构的抵抗弯矩小,外部的弯矩大;(2)结构的内、外弯矩不平衡引起剪力增大。通过一些结构截面不匹配引起的结构破坏案例,讨论了结构截面不匹配和不平衡弯矩引起的结构弯矩不平衡问题。

All internal and external forces( axial force,shear,moment and torsion) of the structure should be balanced,otherwise the structure will be destroyed and collapsed. There are two kinds of unbalanced moments in the structure:( 1) the cross-section of the structure is not matched,the resistance moment of the structure is small,and the external moment is large;( 2) the shear force increases due to the unbalanced internal and external bending moments of the structure. Based on some structural failure cases caused by mismatched cross sections,the unbalanced moments caused by mismatched cross sections and unbalanced moments are discussed.