基于解析刚度模型的钢筋混凝土框架结构二阶效应分析

SECOND ORDER EFFECT ANALYSIS OF REINFORCED CONCRETE FRAMES BASED ON ANALYTICAL STIFFNESS MODEL

考虑材料非线性和几何非线性对钢筋混凝土框架进行了结构承载力分析。在结构承载力分析过程中,考虑混凝土的拉伸硬化作用,根据欧洲规范等效曲率公式提出了解析刚度计算模型;根据变形协调条件,考虑框架结构P-?效应和杆件P-?效应得到杆件的侧向变形计算公式。该文利用提出的解析刚度计算模型和框架结构侧向变形公式实现了框架弯矩重分布。将该文提出的方法的计算结果与已有的试验结果对比表明:该方法可行,框架弯矩和侧向挠曲变形随荷载增大呈现明显的非线性。

The load capacity of reinforced concrete frames is investigated considering the material and geometrical nonlinear characteristics. An analytical stiffness model for reinforced concrete frames is presented based on the equivalent curvature formula derived from Eurocode. The tension stiffening of concrete is taken into account within the analytical stiffness model. Based on the deformation compatibility condition, the deflection equations are derived considering the P-A effect and P-8 effect. The moment redistribution in the frame is achieved based on the proposed analytical stiffness model and the deflection equations. Comparison with test data illustrates that the proposed load capacity evaluation method is feasible and the bending moment and lateral deflection of the frames increase nonlinearly with the increase of the bearing load.