通过三维有限元分析,研究整体现浇预应力混凝土桥墩动力开裂特性。采用双直线钢筋模型和Kent—R.Park混凝土模型,不考虑混凝土和钢筋之间的黏结和滑移,建立分离式有限元模型。对比分析了普通钢筋混凝土墩柱和预应力钢筋混凝土墩柱在地震荷载下的开裂特性。分析结果表明,增加预应力钢束,能够减小墩柱的受拉区域,降低了混凝土的拉应力,推迟了模型裂缝的出现,并且减小墩顶变形。 Through the three-dimensional finite element analysis, the dynamic cracking behavior of the whole cast-in-place prestressed concrete piers is studied. Using the bilinear reinforcement model and the Kent-R.Park concrete model, a separate finite element model was established without regard to the bond and slip between concrete and steel. The cracking characteristics of ordinary reinforced concrete pier and prestressed reinforced concrete pier under earthquake load are analyzed. The analysis results show that adding prestressed steel strands can reduce the tension area of ​​pier and concrete, reduce the tensile stress of concrete, delay the appearance of model cracks and reduce the deformation of pier top.