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厚度的修正

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钢结构的疲劳强度在一定程度上由该节点的板厚以及板厚方向上的应力分布梯度决定。

在比较的厚钢板焊接过程中,焊缝附近极易行成初始缺陷,这就导致结构的连续性下降,从而使缺陷附近存在应力集中现象。

同时应力较大的区域一般用较厚的钢板,也大多选用屈服强度较大的高强钢,而其较高的屈服强度也大大限制了结构塑性变形吸收能量的效果。

因此,当结构板厚大于 25mm 时,S-N曲线需引入厚度修正,修正后的S-N曲线如下:

          

其中,th为节点处的板厚;a1和m为S-N曲线的参数。 

来源:智慧强学斋
疲劳焊接
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首次发布时间:2025-03-12
最近编辑:19天前
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