Stability evaluation of geotechnical structures using numerical limit analysis
Carlos Eduardo Couto Conegundes1; Aldo Durand Farfán1
1 Universidade Estadual do Norte Fluminense - UENF
doi:10.20906/CPS/CILAMCE2017-0824
Resumo
In the field of geotechnical engineering, the study of stability problems is related to the study of the loads and conditions that lead the structures to the imminent state of collapse. Problems of slope stability, foundations, earth pressure and stability of the tunnel face excavations, for example, are generally considered in this category. In this context, several methods have been developed in order to predict the collapse load and the behavior of the structure in its imminence. Among these methods, the Limit Analysis that is the object of this work is highlighted. This method, developed in the 1950s, has a consistent basis on concepts of Plasticity theory. Tough the theorems that underlie it are conceptually simple, analytical evaluation was limited to specific and simple cases. With the development of numerical methods, especially the Finite Element Method (FEM), the Limit Analysis was renamed Numerical Limit Analysis (NLA), which enabled the simulation of problems with different geometries and loading conditions. The work presents the stability analysis of geotechnical structures using NLA, whose main objective is to determine a factor that increases loads. This factor can be understood as a variable that maximizes the loads acting on the system until the imminent collapse of the structure. It is, therefore, a problem of mathematical programming, in which an optimization process is performed to solve the problem. Thus, an algorithm was developed in the MATLAB environment for application of the method. The results obtained through the algorithm were compared with results found in the technical literature.
Palavras-chave: Numerical limit analysis; MATLAB; Finite Element Method