【摘要】 为了模拟重力坝在强震作用下的破坏过程,利用扩展有限元框架下的分离裂纹模型描述混凝土中的裂纹扩展。该模型通过富集非连续位移模式使得对裂纹的几何描述独立于网格边界。利用动力扩展有限元法,提出了集中质量矩阵处理方案,并在通用软件ABAQU S上进行了嵌入。对印度K oyna重力坝在强震下的开裂过程,应用该方案进行了数值模拟。结果表明:用该方案求解非连续界面动力接触问题,既不损失精度,又能避免不稳定性。更多还原

【Abstract】 A discrete crack model based on the extended finite element method(XFEM) was used to describe the nonlinear fracture of concrete gravity dams during earthquakes.The Heaviside function was added to the approximation so the representation of the discontinuities is independent of the mesh boundaries to accurately model the crack growth.The XFEM for the static and dynamic analyses was then embedded into the ABAQUS platform using a concentrating mass matrix scheme.The seismic fracture of the Koyna gravity dam in India was simulated as an example.The results show that the scheme enhances the solution stability of the dynamic contact problem without significant loss of precision.更多还原