Papers by Keyword: MeshFree

Abstract: For the purpose of construction an effective element model, the US- FE-LSPIM TRI3 element formulation, which is based on the concept of unsymmetric finite element formulation, is established. Classical linear triangle shape functions and FE-LSPIM TRI3 element shape functions are used as test and trial functions respectively. Classical linear triangle shape functions fulfill the requirements of continuity in displacement field for test functions. The FE-LSPIM TRI3 element shape functions synthesize the individual strengths of meshfree and finite element methods so they are more proper for trial functions. The element is applied in free vibration analysis of two dimension solids. Typical benchmark problems are solved. The results show that this element is more accurate and capable of good performances under both regular and irregular meshes.

Abstract: A new formulation of triangle element is developed. Based on the concept of unsymmetric finite element formulation, classical linear triangle shape functions are used as test functions, and FE-LSPIM TRI3 element shape functions are used as trial functions. The former is fulfill the requirements of intra-element and inter-element continuity in displacement field, and the latter is a good alternative for requirements of completeness in displacement field. Typical test problems for static solids are analyzed. The results show that the proposed element has good accuracy, and is superior to classical linear triangle element and isoparametric quad element.

Abstract: This US-FE-LSPIM QUAD4 element is formed by using two different sets of shape functions for the trial and test functions, viz. sets of FE-LSPIM QUAD4 element shape functions and sets of classical isoparametric shape functions. For some test problems, the US-FE-LSPIM QUAD4 element has good accuracy. And by compared with FE-LSPIM QUAD4 element, the proposed element does not need to use Penalty method or Lagrange multiplier method to ensure fulfilment of exact essential boundary condition along the entire length of the edge. This paper further studies the performance of US-FE-LSPIM QUAD4 element on mesh distortion. Numerical test examples show that the element exhibits high precisions even under the mesh distortions. The US-FE-LSPIM QUAD4 element displays good tolerance to the mesh distortions

Abstract: A sliding block model is developed for predicting the runout of high-speed landslides, which couple with SPH method (Smoothed Particle Hydrodynamics) to simulate impulse wave. This model adopts the limit equilibrium analysis approach to simulate the whole travel process of the soil mass from the onset of the landslide. The submarine landslide produces highly unsteady and rapidly varied flows, so it was very complicated by fixed grid numerical simulations. The SPH method is a meshfree particle-based Lagrangian method. A sample test is given which shows the impulsive waves generated by high-speed landslide can be reproduced well.

Abstract: A Meshfree approach for continuum damage modeling of 3D orthogonal woven composites is presented. Two different shape function constructions, Radial basis (RB) function and Moving kriging (MK) interpolation, are utilized corresponding with Galerkin method in the Meshfree approach. The failure of two different unit cell models, straight-edge and smooth fabric unit cell model respectively, is compared.

Abstract: . In this paper a variational technique is developed to calculate stress intensity factors with high accuracy using the element free Glerkin method. The stiffness and mass matrices are evaluated by regular domain integrals and the shape functions to determine displacements in the domain are calculated with radial basis function interpolation. Stress intensity factors were obtained by a boundary integral with a variation of crack length along the crack front. Based on a static reference solution, the transformed stress intensity factors in the Laplace space are obtained and Durbin inversion method is utilised in order to determine the physical values in time domain. The applications of proposed technique to two and three dimensional fracture mechanics are presented. Comparisons are made with benchmark solutions and indirect boundary element method.