Estudo de estabilidade da frente de escavação de túneis rasos em solo

• Ano de defesa: 2014
• Autor(a) principal: Matheus de Oliveira Rocha
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Plaxis 3D; Frente de escavação; Túneis; Estabilidade; Análise limite; Mecânica do solo; Escavação
• Link de acesso: http://hdl.handle.net/1843/BUOS-9RWJQN

The increasing use of the underground in large cities for both locomotion of people, as to the development of services such as sanitation, flood control and water transport, in general have contributed to the increase of the tunnel excavation in unfavorable geological conditions. Therefore, the studies of tunnels bored in soils of low resistance have intensified lately. The concern with the front of a tunnel driven in this type of soil has enlarged, since in most urban tunnels the collapse strength of the soil does not meet the conditions of stability for the full face excavation. In the present research, the analysis of the face stability of tunnels were presented by empirical observational models, mathematical models based on the theory of Plasticity for limit analysis and the use of the finite element method. The latter method has been widely used, however, they still require powerful computers and considerable computational time for generating results. The use of simpler mathematical models can be useful in engineering practice as in the interpretation of the behaviour of the soil (determination of FS) and even to identify which situations require more insightful analysis or not. This study presents a comparison of some methods of analysis of the stability of the tunnel face excavated in soil, using the analytical, mathematical models based on the theory of Plasticity limit analysis proposed by Leca and Dormieux (1990) and Mollon (2009), and the finite element method through the Plaxis 3D software. The results found that, in relation to the finite element method, the model of Leca and Dormieux proved to be less conservative, while the results presented by the method of Mollon et al. proved quite satisfactory and useful for practical use.