Dynamic method for determining critical loads in the PRINS computer program

Relevance. Buckling analysis is important in the design of buildings and structures. It is used in various fields of engineering - mechanical engineering, aircraft and shipbuilding, civil engineering, etc. Until the second half of the twentieth century, mainly analytical methods of buckling were applied in practice. With the appearance of computers, numerical methods, in particular, the finite element analysis, began to prevail. Buckling analysis was implemented in programs of finite element analysis, such as NASTRAN, ANSYS, ABAQUS, ADAMS, DIANA, and others. In view of great responsibility, buckling analysis of structure should be carried out using at least two different programs. However, due to the high cost of software products, not all project organizations are able to have a number of programs. An alternative is to develop programs that can complete buckling analysis using several methods. This would increase the reliability and quality of calculation results. The PRINS computer program has opportunity for buckling analysis using two methods - static and dynamic. The aims of the work - to show the theoretical aspects and practical implementation of the dynamic principle of buckling analysis in buildings and structures using finite element method, as well as to give the algorithm implemented in the PRINS program and the results of verification calculations confirming its reliability. Results. The algorithm presented in this article and implemented in the PRINS computer program allows to determine critical loads using a dynamic buckling criterion. On the basis of numerous verification calculations, it was established that the implemented algorithm was effective for determining critical loads in frame, thin-walled and ribbed plate structures. The use of the PRINS computer program enables to use an alternative method for determining critical loads for a wide class of engineering problems in addition to the classical (static) method.