Aplicação de modelos numéricos para estimativa de recalques deuma célula do Aterro Sanitário de Belo Horizonte

• Ano de defesa: 2010
• Autor(a) principal: Fabio Henrique Rodrigues da Silva
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Resíduos sólidos urbanos; Recalques; Modelagem numérica; Aterros sanitários; Geotecnologia ambiental; Compressibilidade; Meio ambiente; Resíduos sólidos; Engenharia sanitária; Saneamento
• Link de acesso: http://hdl.handle.net/1843/FRPC-8DQGLW

This study presents the application of a coupled mechanical and biological one-dimensional model, developed by Simões (2000), and two-dimensional linear and non-linear (hyperbolic) elastic models to assess settlements in municipal solid waste landfills. In the model of Simões (2000), the vertical settlements are obtained by two components: a mechanical, due to the application of loads and the viscous behavior of the waste, and a biological, resulting from waste biodegradation processes. The model considers the properties of the waste fractions, enabling the analysis of problems where composition and operating conditions vary with time. The elastic models use two-dimensional theory of elasticity parameters and enable the modeling of horizontal displacements; however, they do not incorporate the portion of settlements resulting from biodegradation processes. The models were used in the calibration and simulation of Cell AC-05, at BR-040 Landfill in Belo Horizonte/MG. Initially, filling history and settlements records, obtained from a comprehensive geotechnical and operational monitoring program, were organized. Initial estimates of the elastic parameters of waste were obtained in the literature. Then, calibration and simulation were carried out, aiming at assessing the performance of the models in the prediction of long-term settlements and increase in volume during filling. A discussion of aspects that should be incorporated in the interpretation of monitoring record for a best estimate of settlements and evaluation of geotechnical stability conditions are also presented. The one-dimensional model showed good results for vertical settlements with only 5 out of 28 settlement plates presenting differences between measured and simulated values higher than 30%. The two-dimensional elastic models have not provided satisfactory results for prediction of long-term settlements. Concerning the increase in volume or gain in lifespan during the filling phase, the results were satisfactory. In the field, a 28% increase in volume was observed during the filling phase, compared to 30% obtained in the simulation with the non-linear elastic model (hyperbolic) and 33% obtained with the one-dimensional model, suggesting the applicability of this model. It was also noted the importance of considering the time between the construction of waste layers and the start of settlement monitoring. When considered this aspect, specific vertical deformations with a more uniform behavior were obtained.