User's manual for preprocessor computer programs for preparing input data for the finite element structural analysis program SAPIV (programs SPREP, COMBINE, FINAL8). [For CDC computers

Abstract

A finite element structural analysis program such as SAPIV can require a large amount of effort in data preparation, particularly for three-dimensional structural models and two-dimensional cases of complicated geometry. The development of a self-organizing quadrilateral mesh generator such as QMESH has made it possible to reduce significantly the amount of manual data preparation for SAPIV. The mesh description generated by QMESH can be transformed into appropriate card images for input to SAPIV by means of the preprocessor, SPREP. Two types of element generation are available in SPREP: quadrilateral elements for two-dimensional plane or axisymetric problems (Type 4), and 8- or 12-mode three-dimensional elements (Type 8). The Type 8 elements can be generated for the following geometrical cases: a plate, a cylindrical shell section, a spherical shell section, or a toroidal shell section. SPREP can be readily modified by the user to include additional features that are desired. The program produces the bulk of the input data for SAPIV, which includes the nodal point coordinate card images and the element numbering card images. Additional data such as boundary conditions, loads, load multipliers, material properties, etc., are added to the data file by the user. Two other pre-processors described in this manual can be used as an adjunct to SPREP. FINAL8 is used to add boundary elements (Type 7) to the SAPIV input data file. This is particularly useful in the case of three-dimensional structures.FINAL8 will compute and add nodes for boundary elements along the edges of the model specified by the user and will merge all of the boundary element input data into the file. The pre-processor COMBINE is used to integrate SAPIV input data. 6 figures, 10 tables. (RWR)