摘要
针对层状地基,采用改进的比例边界有限元算法(SBFEM)与有限元算法相结合,求解层状地基内刚性埋置管道动力响应问题。改进的比例边界有限元算法引入一个新的坐标变换关系,以一条相似轴代替传统SBFEM的相似中心,并利用加权余量方法得到层状地基动力刚度矩阵方程,最后与有限元法在远场和近场交界面进行耦合,由此求得层状地基埋置管道的动力响应。数值算例验证了算法的准确性,并利用该算法分析了层状地基的非均质特性、泊松比以及埋置深度对管道动力响应的影响,以期为工程实际提供必要的数值依据。结果表明:地基的非均质特性和泊松比对埋置管道的动力响应均有显著的影响;随着埋置深度的加大,管道在相同荷载作用下的动力响应均减小。
In this paper, an improved scaled boundary finite element method(SBFEM) is used to solve the dynamic response of rigid buried pipe in multi-layered soil combined with finite element method. A new coordinate transformation relation is introduced into the improved SBFEM, with a similar line instead of the similar center in traditional SBFEM. Then the dynamic stiffness matrix equation can be obtained by using weighted residual method for multi-layered soil. Finally, the dynamic stiffness matrix is coupled with finite element method at the boundary between the near field and far field to solve the dynamic response for rigid buried pipe in multi-layered soil. The comparison with an existing solution validates the accuracy of the proposed method. And the influence of heterogeneity characteristic of layered soil, Poisson's ratio and buried depth on the dynamic response of the buried pipe is further investigated through a parametric analysis which provides the necessary numerical basis for the engineering practice. As the results show, the heterogeneity characteristic of layered soil and Poisson's ratio have significant influence on the dynamic response of the buried pipeline. With the increase of the buried depth, the dynamic response of the pipeline under the same load decreases.
引文
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