【摘要】 基于比例边界有限元法(scaled boundary finite element method,SBFEM)对结构-无限地基系统进行了频域的动力相互作用分析。通过一种新的高阶透射边界对无限地基进行模拟,该透射边界是基于无限域动力刚度矩阵的连分式解形式,连分式的系数通过以动力刚度矩阵表示的比例边界有限元方程递推计算。通过数值算例验证了该高阶透射边界的收敛性,并与解析解进行了比较,表明该方法具有较高的精度。最后对重力坝-库水-无限地基系统进行了频域分析,将计算结果与无质量地基模型进行了对比。对比结果表明,所提地基模型计算的结果与无质量地基模型的计算结果相比降低约20%。该方法可以有效地进行二维和三维大型结构-地基相互作用分析。更多还原

【Abstract】 The analysis of structure-unbounded foundation dynamic interaction in frequency was made using the scaled boundary finite element method( SBFEM). The unbounded foundation was modeled by a new high-order transmitting boundary based on the continued-fraction solution of the dynamic-stiffness matrix. The coefficient matrices of the continued fraction were evaluated recursively through the scaled boundary finite element equation expressed in dynamic stiffness matrix. The convergence of the high-order transmitting boundary is demonstrated by the numerical examples. Comparisons with the analytical solutions reflects higher accuracy of the method. Finally,frequency-domain analysis was carried out for the system of the gravity dam-reservoir-foundation and the results were compared with the mass-less base model. Results indicate that the approach is effective and suitable for 2D and 3D large-scale structure-foundation interaction analysis.更多还原