Global–Local Non Intrusive Analysis with 1D to 3D Coupling: Application to Crack Propagation and Extension to Commercial Software

Abstract

Computational simulation is a highly reliable tool used to solve structural analysis problems. In recent times, several techniques have been developed in the field of computational mechanics in order to analyze non-linearities in less time, helping decision-making when structures suffer damage. The global–local analysis is a technique to increase the efficiency of computational simulations by using a global model to obtain boundary conditions in a coupling zone imposed on a local model. Coupling can be performed through the primal–dual method, which is used for crack propagation using 2D and 3D models with fine meshes, thus saving computational time. However, it has not been implemented at a commercial level to analyze large structures such as multi-story buildings with focused non-linearities. In this work, a global–local analysis with non-intrusive methodology and simplified models was implemented in a cracked framed structure, using a 1D (global) and 3D (local) coupling considering crack propagation with primal–dual interface conditions. Different lengths of the local model were analyzed, studying their influence on the convergence of the problem, and compared with a 3D monolithic model to check the reliability of the results. The results show that the proposed methodology solves the problem with an error less than 10%. Furthermore, it was determined that the dimensions of the local model affect the convergence of the problem. This work also provides an implementation of the method for large structures containing focused non-linearities and using commercial software, reducing computational time for the cracked structural analysis.

Discriminant Analysis Based on the Patch Length and Crack Depth to Determine the Convergence of Global–Local Non-Intrusive Analysis with 1D-to-3D Coupling

“…The coupling of the models is performed using Code-Aster software, communicating the displacements and forces between the global model and the local non-linear model using the comtypes Python library. The complete methodology for coupling 1D frames with 3D elements is presented in [25]:…”

“…This analysis has been used to estimate crack propagation, non-linear hardening behavior, and non-linear contact, among other complex behaviors, with less computational time compared to a non-decomposed model (also known as a monolithic model) [20][21][22][23][24][25].…”

“…In the implementation of global-local non-intrusive analysis with 1D-to-3D coupling performed in [25], it can be seen that the convergence depends on the length of the local model, which is determined by changing the number of iterations and their errors. Therefore, it is necessary to know the optimal dimensions to ensure the convergence of the methodology.…”

“…To validate the results of the discriminant analyses, the three-story building presented in [25] with various patches was analyzed with the following properties: The uncracked inertia in (mm 4 ), uncracked area in (mm 2 ), and complete beam length in (mm) were 95,109,333, 5680, and 10,000 (mm), respectively.…”

“…• Four patches were analyzed with local lengths of 1000, 1500, 2000, and 2500 mm. The SAP2000 model of the software is presented in Figure 10 and was obtained from [25]. The different building cases used for validation are presented in Table 6.…”