预应力混凝土框架次弯矩简化计算方法探讨

对于单跨预应力混凝土框架梁和多跨预应力混凝土框架的内跨梁,通过位移法证明了用一定矢高的单波抛物线代替实际预应力筋进行次弯矩的计算,方法简单,结果准确。对于多跨预应力混凝土框架的边跨梁,由于预应力筋布置形式与内跨不同,采用与单跨梁相同的简化方法进行计算,结果可能会有较大误差,建议按实际预应力筋形状计算。

STUDY ON SIMPLIFIED CALCULATION METHOD FOR SECONDARY MOMENT OF PRESTRESSED CONCRETE FRAME

For single span beam or interior span beam of prestressed concrete frame, a simplified method for calculating secondary moment was developed, A parabola was used instead of real prestressing steel bar shape in this method. The method is easy and the result is accurate. But for side span beam, the method is not accurate enough because the arrangement of prestressing steel bar in side span is different from that in interior span. It is suggested that secondary moment of side span beam should be calculated with its real shape.