【摘要】 为了准确预测预应力混凝土结构的非线性行为,建立了基于纤维截面的预应力混凝土结构组合式分析模型。开发了一种粘结单元模拟预应力筋与混凝土间的粘结滑移,采用基于纤维截面的粘结单元模拟普通纵筋与混凝土的粘结滑移,模型还考虑了材料低周疲劳特性对结构损伤的贡献。利用3组预应力混凝土框架试验对模型进行了验证,结果表明:组合式模型不仅能够反映预应力混凝土结构在往复荷载作用下的强度退化、刚度退化以及捏缩现象,准确预测结构滞回曲线,也能准确地评估预应力混凝土结构在地震作用下的各种动力特性。模型计算量小,收敛性好,可作为预应力混凝土结构非线性分析的有效手段。更多还原

【Abstract】 In order to predict the nonlinear behavior of prestressed concrete structures,a combined model based on the fiber section is proposed.A bond element is developed to simulate the bond-slip behavior between prestressed tendons and concrete,and the fiber section-based bond element is utilized to model that between reinforcing bars and concrete.The contribution to structural damage due to the low cycle fatigue property of materials is also considered.The proposed model is illustrated by three tests of prestressed concrete frames.The results show that the model is able to carry out the strength degradation,stiffness degradation and pinch phenomenon of structures under the cyclic loading,which conclude the exact hysteretic curve.It can also evaluate the dynamic properties of prestressed concrete structures under earthquakes.Because of the advantages of less computational effect and better convergence,the model can be used for the nonlinear analysis of prestressed concrete structures.更多还原