【摘要】 构件进入非线性时,塑性区域一般出现在构件的端部,然而目前有限元软件常用的高斯-勒让德积分方法在端部没有求积节点,这将直接影响数值模拟的精度。该文提出在基于力插值的非线性梁柱单元中使用固定端部求积节点的积分方法,并通过OpenSees进行二次开发实现了该方法。实例分析表明,相同的积分点个数,固定一端求积节点的高斯-拉道积分方法和固定两端求积节点的高斯-洛巴托积分方法具有较高的精度,而固定两端求积节点的牛顿-科茨积分方法精度稍低,但均明显优于高斯-勒让德积分方法。建议在非线性分析中采用高斯-拉道积分方法或者高斯-洛巴托积分方法。更多还原

【Abstract】 The plastic hinge area generally appears at the ends because of the nonlinear material response of beam–column members,but there is no integration point fixed at the end of the element for Gauss-Legendre Integration that is commonly used in FE programs.So an integration method for the fixed integration point at the ends of the element is proposed and developed based on OpenSees.The study case shows that the result of Gauss-Radau integration(it places an integration point at only one end of the element) and Gauss-Lobatto integration(it places an integration point at each end of the element) is better than the result of Newton-Cotes integration(it also places an integration point at each end of the element),but they all perform better than the result of Gauss-Legendre integration.It is suggested to use Gauss-Radau integration or Gauss-Lobatto integration in the nonlinear analysis.更多还原