组合构件包括两种不同混凝土组合而成的截面或混凝土与钢组合的结合截面，由于混凝土具有徐变性能，各组合部分徐变不同会引起截面内的应力重分布，从而导致截面内的附加应力。本文从引起徐变附加应力的原因——组合截面的变形协调关系出发，推导出了计算徐变引起的截面应力重分布的附加内力的微分方程，并提出了各种组合截面的徐变的截面应力重分布的计算公式。

Different creep coefficients of concrete layers in composite beam will cause redistribution of stress and additional stress in section. Based on the concept of strain compatibility approach, in this paper,the authors deduced a differential equation of the additional inner forces resulted from creep. Thereafter, the authors proposed an equation to calculate stress redistribution of steel and concrete composite beam, concrete composite beam and concrete strengthening member. At last, the formulas of additional stress of the section were proposed.

TU398.9