Kratos Dem, a paralel code for concrete testing simulations using the discrete element method

Abstract

This dissertation is the result of the implementation of a Discrete Element Method code in an open source object-oriented software platform called Kratos developed in CIMNE (Barcelona).

After the introduccion and the objectives, a brief review on the Discrete Element Method in its basic conception is presented in the third chapter of the document while the theoretical developments and discussions for the application of the method to continous media, specially to conctrete testing simulation, can be found in the fourth chapter. Also here, special attention is paid to the capabilities of this method when it is applied to continuous media; several numerical analisis are performed here to show the possibilities and limitations of the method in the fifth chapter. In the sixth chapter, the Kratos framework is introduced and the basic structure of the developed application is explained. The implementation of the utilities that permit, from a user-friendly interface, perform concrete test simulations can be found here. Furthermore, the possibilities and advatages that the Kratos framework provides the DEM-Application are shown as well as examples of how the code behaves in terms of High Performance Computing. Additionally, examples of coupling of this application with other codes and work done by other researchers in the institution are here presented. In the seventh chapter, the results of the different concrete simulation tests can be found as a verification of the code comparing with the results obained by Dempack. Finally, in the last chapter some conclusions and future work is presented. The objective of the KDEM, in its conception, was to have a base program for the DEM coded in a very powerful and versatile platform, the open-source multiphysics code Kratos. This permits different researchers extending and improving the code as well as using as a closed package for projects and simulation by advanced users and engineers. Previous to this, in CIMNE, another code based on the Discrete Element Method has been used for engineering projects, Dempack. When the KDEM code started the purpose was to provide CIMNE a general DEM application able to be parallelized and to be combined with other fluid or structure applications. At the same time, a lot of implementation has been done in order to substitute, and improve if possible, the existing code Dempack; part of this thesis focuses on the concrete test simulation, a field where CIMNE has currently projects ongoing. The result of this work accomplishes the objective of providing Kratos a general purpose paralelizable Discrete Element Method application which is the of the interest of CIMNE. In a second term, it presents the first promising results in the field of Concrete Test Simulation, following the objective of substituing in the future, the existing application, Dempack.