Adaptive mesh refinement of upper bound finite element method and its applications in geotechnical engineering

The grid discretization error is the main source of calculation error of finite element upper bound limit analysis. To optimize the calculation mesh and reduce the numerical discretization error, an adaptive mesh refinement strategy is proposed based on the advancing front grid generation technique and taking the relative value of elemental energy dissipation as control index. Firstly, the advancing front grid generation technique is introduced to gain a more flexible control of sizes and shapes of elements during the mesh generation process. Secondly, the relative value of elemental energy dissipation in the current mesh is transformed into the distribution information of element sizes in the new mesh, and then this information is used to indicate the new mesh generation, which successfully realizes the optimization of calculation mesh of finite element upper bound limit analysis. Finally, the effectiveness of the proposed method is verified by example analysis.