系列学术报告题目：
(1)From Geometric Modelling to Numerical Simulation:
An Automated Approach
(2) The Scaled Boundary Finite-Element Method:
Topic I: Recent and Future Developments
( 3) The Scaled Boundary Finite-Element Method:
Topic II: Application to Fracture and Crack Propagation
报告人：Chongmin Song 教授
时 间：报告（1）11月16日上午9:30点~11:30点，下午2:00-4:00 讨论。
地 点：河海大学江宁校区力材楼327房间
时 间：报告（2）、（3）11月17日、18日上午9:30-11:30，下午讨论。
地 点：河海大学江宁校区力材楼1116房间
主办单位：力材院计算力学研究所
报告人简介：
Prof. Chongmin Song(宋崇民)，澳大利亚新南威尔士大学土木与环境工程学院教授。Prof. Song主要从事比例边界有限元、断裂力学、波动传播、结构动力学与地震工程等方面的研究。1996年他与瑞士联邦理工学院的Wolf J.P.教授共同创立了比例边界有限元法（Scaled Boundary Finite Element Method, SBFEM）。这种新型数值方法兼具了有限元法与边界元法的优点同时又避免了其缺点，其主要特点包括精度高、计算量节省，并且在处理无限域问题和应力奇异性方面具有突出优点。近年来在International Journal for Numerical Methods in Engineering、Computers & Structures、Computational Mechanics、International Journal of Solids and Structures、Earthquake Engineering and Structural Dynamics等国际著名期刊上发表论文100余篇，合著《Finite-Element Modelling of Unbounded Media》（Wolf J. P. and Song Ch., 1996）、《The semi-analytical fundamental-solution-less scaled boundary finite element method to model unbounded soil》（Wolf J. P. and Song Ch., 2003）两部。主持澳大利亚研究委员会等基金项目10余项。
报告摘要：
1）From Geometric Modelling to Numerical Simulation:
An Automated Approach
In this talk, a technique to fully automate the numerical modelling and simulation process will be presented. The development is underpinned by our recent research on constructing general polytope (polygon in 2D and polyhedron in 3D) elements based on the scaled boundary element method. The polytope elements can have any number of faces, edges and vertices and offer a much higher degree of flexibility in mesh generation. This allows the development of a polytope mesh generator based on the simple and efficient quatree/octree algorithm. Geometrical models provided as CAD, STL and digital imaging files can be handled in a unified approach. The whole analysis process is fully automatic. The efficiency, robustness and some salient features of the proposed technique are demonstrated with numerical examples and demonstrations. Potential research and applications of this novel technique will be discussed.
2) The Scaled Boundary Finite-Element Method:
Topic I: Recent and Future Developments
This talk will start with a brief theoretical background of the scaled boundary finite element method so that the salient features of this method can be appreciated. Some recent advances in the fundamental theory are summarised. Applications in the area of dynamic soil-structure interaction, fracture mechanics, elasto-plasticity, piezoelectric composites, Lamb waves, and plate analysis will be presented to demonstrate the accuracy and efficiency of this technique in solving problems challenging to standard numerical methods. The current research activities of the speaker’s group on the development of a full automatic procedure for computer simulations directly from CAD models and digital images will be introduced. Challenges and directions of further developments will be discussed.
3）The Scaled Boundary Finite-Element Method:
Topic II: Application to Fracture and Crack Propagation
The scaled boundary finite element method provides an attractive approach for fracture analysis including crack propagation. The semi-analytical solution accurately represents the stress field around a singular point (e.g. a crack tip, a V-notch or a multi-material corner). A unified definition of generalized stress intensity factors is proposed based on this semi-analytical solution. The generalized stress intensity factors and the T-stress are computed directly from their definitions by using a stress recovery technique in the finite element method. When modelling crack propagation, the problem domain is divided into a polygon mesh. The crack path is modelled by simply splitting a polygon element into two smaller ones. Unlike the extended finite element method, no enrichment is required for discontinuities and singularities. High-order elements can be constructed straightforwardly. The accuracy and simplicity of the scaled boundary finite-element method in fracture analysis are demonstrated by numerical examples.
