预应力混凝土梁非线性分析单元模型

为了能够准确有效地分析混凝土梁中预应力钢筋的力学性能,模拟结构中存在的普通钢筋、预应力直线钢筋和预应力曲线钢筋,提出了一种预应力混凝土梁非线性分析的单元模型。应用有限元理论,采用全拉格朗日列式的三维杆单元模拟预应力钢筋;采用实体退化组合壳单元模拟结构;应用钢筋单元和混凝土单元之间的位移场关系形成钢筋对混凝土单元的贡献,将预应力钢筋对结构的作用直接反映在单元模型内部。预应力混凝土T梁的破坏过程模拟结果表明梁的跨中挠度计算结果和试验实测数据吻合,单元模型有效地反映了预应力束的力学性能。

Nonlinear analysis element model of prestressed concrete beam

In order to analyze the mechanics properties of tendon exactly and effectively,simulate normal steel bar,linear tendon and curved tendon in prestressed concrete beam,a nonlinear analysis element model of prestressed concrete beam was presented.In the model,based on finite element method,tendon was simulated by 3-D link bar element of total Lagrangian method,solid degenerated-combined shell element was used to simulate prestressed concrete beam,and the stiffness of link element contributing to concrete element was computed according to the displacement relationship of tendon element and shell element,the action of tendon contributing to the structure was directly reflected inside the element.The simulation result of the destroyed process of prestressed concrete T beam shows that the computation deflection and test deflection in middle span are accordant,and the model can simulate the mechanics properties of tendon.2 tabs,8 figs,14 refs.