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受弯构件计算时,受压区应力图形用矩形代替曲线的原则是什么?

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正确答案:

1.等效矩形应力图形的面积与理论图形(即二次抛物线加矩形图)的面积相等,即压应力的合力大小不变;

2.等效矩形应力图的形心位置与理论应力图形的总形心位置相同,即压应力的合力作用点不变。

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