预应力组合梁的极限承载力计算

Ultimate capacity investigation of prestressed composite beam

采用塑性分析法分析了预应力组合梁在极限状态下的受力性能.根据塑性中和轴的位置把梁的截面分为2类,分别给出了它们的判别条件和抗弯承载力的计算公式,以此确定构件的承载力.计算结果表明,在最大偏心距相同情况下,直线布置、梯形布置和三角形布置的极限承载力相同;预应力组合梁比普通组合梁的极限荷载可提高27.7%;钢梁屈服强度提高,梁的极限荷载也随着提高.

This paper examines the ultimate behavior of prestressed composite beams by plastic analysis method.The sections of beams are divided into two types based on the location of plastic neutral axis.The definition and calculating formulae of flexural resistance are given to determinate the ultimate capacity of the beams respectively. The results show that the ultimate capacities are equal under the same maximum eccentricity when the shape of the wires layout is linear,trapezoid or triangular.The ultimate capacity of prestressed composite beams is 27.7% higher than that of reinforced concrete ones.Moreover, the ultimate load of steel beams also increases.