Estudo da estabilidade de valas escoradas por equilíbrio-limite e pelo método dos elementos finitos

Abstract

This work examines the behavior of strutted excavations by means of different methods. Chapter 2 presents a review of the methods available for the stability analysis of excavations: the methods fall into three main cathegories, namely (a) simple (or "empirical") methods, (b) limit-equilibrium methods and (c) the Finite Element Method. In the section on limit-equilibrium methods, a proposal to account for the strut loads (which improve the stability) in the evaluation of the factor of safety of strutted excavations is put forward. Chapter 3 contains a parametric study of the stability of strutted excavations by the Bishop’s Simplified Method. A comparison between the factor of safety calculated by this method and those computed according to Tschebotarioff and Terzaghi (empirical methods) is also included. Chapter 4 contains a parametric study of strutted excavations by the Finite Element Method in which a linear elastic model was used. A comparative study between the factor of safety against the overall (basal) failure by the FEM and by the Bishop’s Simplified Method is included. Chapter 5 presents the analysis of an excavations for the Rio de Janeiro Subway by the Finite Element Method. The analysis used a non-linear elastic model.