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Mechanical Engineering

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Bending

Bending Stages of Elastoplastic Members

Description

Elastoplastic members under bending show a clear change in stress as the load increases. For a rectangular cross-section, the first response is elastic. The stress follows Hooke's Law and forms a linear pattern across the section.

In this early stage, stress grows from the neutral axis to the out...

Transcript

考虑一个由弹塑性材料制成且具有矩形横截面的构件。在弹性极限内,该截面上的应力分布呈线性。

随着弯矩的增大,构件中的最大应力也随之增加。当构件的变形仍保持完全弹性时,可观察到最大弯矩。

通过代入截面的惯性矩与截面长度的比值,可计算该截面的最大弹性弯矩。

随着弯矩进一步增大,塑性变形在上下区域均匀发生,但应力大小相反。塑性区域内部存在弹性核,弹性核的应力随厚度呈线性变化。 

可根据最大弹性力矩方程,通过解析方法估算弹性核心内应力所对应的弯矩。

当弯矩进一步增加至极限值时,变形完全变为塑性,构件的塑性弯矩可用最大弹性弯矩来表示。