【摘要】 通过对 782块先张法预应力混凝土板的检测和其中 3块板的结构实验 ,深入地分析了这批预应力混凝土板的反拱较为分散的原因 .分析表明 ,其中最主要的原因是预应力钢绞线有效预应力值不准确 .分析还表明 ,对于预拉区出现裂缝的预应力混凝土板计算反拱时 ,应考虑裂缝对其截面刚度的影响 .更多还原

【Abstract】 On the basis of the inspection on 782 pre stressed concrete hollow slabs and the structural tests of 3 ones, a thorough analysis on the causes of the dispersion of reversed deflection of the ones is made. The analysis shows that the most important cause is the dispersion of the effective pre stresses of the pre stressed strand. The analysis also shows that the cracks in pretension area of the pre stressed concrete members have an important effect on the stiffness of the members, therefore the effect on the stiffness of pre stressed concrete member must be taken into account when the reversed deflections of the ones are predicted.更多还原