论文部分内容阅读
利用共旋坐标法提出了一种预应力钢筋混凝土梁非线性分析的混合单元模型,在随转坐标系内,采用分层梁单元来模拟混凝土结构,带初应变的杆单元来模拟预应力钢筋,预应力钢筋杆元和混凝土梁元的变形协调则通过非线性刚臂来实现,通过刚臂单元两端节点位移和力的关系形成预应力钢筋对混合单元刚度矩阵的贡献,从而导出随转坐标系下预应力混凝土梁考虑材料非线性的切线刚度矩阵,几何非线性则由单元随转坐标系到结构坐标系的转换矩阵及其微分来体现,从而获得结构坐标系下混合单元模型的几何与材料双非线性切线刚度矩阵。数个钢筋混凝土及预应力钢筋混凝土梁非线性分析算例表明:所提出的混合单元模型能较好地分析预应力钢筋混凝土梁非线性性能,具有一定的实用价值。
In this paper, a hybrid element model of nonlinear analysis of prestressed reinforced concrete beams is proposed by using co-rotating coordinate method. In the coordinate system of turning, a stratified beam element is used to simulate the concrete structure. The rod element with initial strain is used to simulate prestressed reinforcement , The deformation coordination of prestressed steel bar element and concrete beam element is realized by nonlinear rigid arm, the contribution of prestressed steel bar to the stiffness matrix of hybrid element is obtained by the relationship between the displacement and force of nodes at both ends of rigid arm unit, Considering the nonlinear tangent stiffness matrix of the prestressed concrete beam in the coordinate system, the geometrical nonlinearity is represented by the transformation matrix of the unit with the coordinate system to the structural coordinate system and its derivative, so that the geometry of the mixed unit model in the structural coordinate system Double Nonlinear Tangential Stiffness Matrix with Materials. The nonlinear analysis examples of several reinforced concrete and prestressed reinforced concrete beams show that the proposed hybrid element model can well analyze the nonlinear behavior of prestressed reinforced concrete beams and has certain practical value.