论文部分内容阅读
框架单元常受绕横截面弱轴的弯矩作用,如空间框架单元、绕弱轴屈曲的压杆等。在某些组合截面柱中,绕弱轴方向的弯矩最大。建立简化模型,研究受轴压且绕弱轴弯曲时钢框架单元的二阶非弹性性能。建立了受轴压且绕弱轴弯曲时工字钢、H型钢的塑性强度公式及切线模量经验公式。切线模量公式可用于计算切线刚度,进而求得内部恢复力。这些公式可用于分析钢构件,并考虑欧洲规范ECCS中提到的残余应力,借助有限元程序,采用这些公式,分析平面框架的非弹性二阶性能。与纤维模型相比,新建立的模型的相关性更好。结果表明:新模型准确度高,能节约大量迭代计算时间,
Frame elements are often subject to bending moment around a weak axis of the cross-section, such as space frame elements, buckles flexed about a weak axis, and the like. In some combined columns, the bending moment in the direction of the weak axis is the largest. A simplified model was established to investigate the second-order inelastic behavior of steel frame elements under axial compression and bending around the weak axis. The empirical formulas of plastic strength and tangent modulus of I-beam and H-beam under axial compression and bending around the weak axis are established. Tangent modulus formula can be used to calculate the tangent stiffness, and thus find the internal resilience. These equations can be used to analyze steel components and to consider the residual stresses mentioned in the European Code ECCS. Using the finite element program, these formulas are used to analyze the inelastic second-order performance of planar frames. The new model is more relevant than the fiber model. The results show that the new model has high accuracy and can save a lot of iterative computation time.