The Implementation And Application Of OOPFEM Element Re-subdivision Algorithm

Nowadays structural calculation and analysis using compute are more and moreimportant in the field of structural engineering. Application of FEM is most extensive,which is use in almost all of fields of construction and fluid, thermal transmittance,electromagnetic field. With diversification of problem, processing mode and algorithmcontinually develop. As the programs become bigger and bigger, the defects oftraditional program languages that they have low reusability and maintainability, areexposed. The OOP(Object-Oriented Programming)that appears in later 80s can solvethe problem well and have been applied widely in the field of structural analysis. These following jobs mainly finished using OOP technique on the Virtual C++ inthis article: (1) General introduction of a FEM program frame. Specification of program ofmain class in this frame is presented. Specific handling to some classical problems inthe FEM analysis process used in the frame is specified, which reflect the advantage ofOOP. (2) Classical crack analysis of reinforced concrete is that the crack elements havebeen installed previously at the position the cracks possible appearing and the growth ofcracks have to be along the direction of crack installed previously. However, the data ofFEM analysis, such as elements, nodes, are stored with dynamic lists in this article.With loads increasing, the crack growth tendency could be simulated when analysismodel be modified automatically with old elements automatically subdivided to newelements simultaneously deleted. According the idea mentioned above, the algorithm ofelement re-subdivision to one of specific element plane-triangle element of threenodes is presented with creating various related classes in the previous FEM analysisframe. (3) Two examples is presented with initiative discussion and evaluation.