In this work the possibility of identifying two important aspects in the process of adopting soil parameters for calculating stability analysis models in tailing dams is discussed. The use of commercial computer progr...In this work the possibility of identifying two important aspects in the process of adopting soil parameters for calculating stability analysis models in tailing dams is discussed. The use of commercial computer programs for stability calculations allows obtaining numerically exact results. Its representativeness, however, will be linked to the correct definition of the phreatic regime and to the prediction of volumetric soil behavior during shearing (contractile vs. dilating materials). The theoretical principles for the selection of soils parameters for different failure models are briefly presented. Also, how the incorrect assumptions regarding material behavior can significantly affect the estimation of tailing dams’ stability. The results of CPTu tests for the diagnosis of the phreatic and mechanical condition of the materials are discussed and two examples are presented to remark on the care that should be taken to avoid incorrect soils parameters adoption.展开更多
The current practice of geotechnical engineering commonly uses a combination of theoretical and empirical correlations to estimate the soil undrained shear strength in clays from the piezocone test. In order to comple...The current practice of geotechnical engineering commonly uses a combination of theoretical and empirical correlations to estimate the soil undrained shear strength in clays from the piezocone test. In order to complement the use of such correlations, the application of a method to estimate the soil undrained shear strength, using measures of the excess pore pressure in dissipation tests of piezocone is presented. In cohesive soils, excess pore pressure and undrained shear strength are dependent on the same variables (stress state, stress history, soil stiffness), which allows them to be related by the theoretical cavity expansion-critical state framework. This paper mentions the mathematical formulation that supports the theoretical framework used, its relationship with the Nkt and NΔu factors and their estimation in a case studied. The results obtained are consistent within the dispersion found in the international literature and encourage the use of the method in engineering practice.展开更多
文摘In this work the possibility of identifying two important aspects in the process of adopting soil parameters for calculating stability analysis models in tailing dams is discussed. The use of commercial computer programs for stability calculations allows obtaining numerically exact results. Its representativeness, however, will be linked to the correct definition of the phreatic regime and to the prediction of volumetric soil behavior during shearing (contractile vs. dilating materials). The theoretical principles for the selection of soils parameters for different failure models are briefly presented. Also, how the incorrect assumptions regarding material behavior can significantly affect the estimation of tailing dams’ stability. The results of CPTu tests for the diagnosis of the phreatic and mechanical condition of the materials are discussed and two examples are presented to remark on the care that should be taken to avoid incorrect soils parameters adoption.
文摘The current practice of geotechnical engineering commonly uses a combination of theoretical and empirical correlations to estimate the soil undrained shear strength in clays from the piezocone test. In order to complement the use of such correlations, the application of a method to estimate the soil undrained shear strength, using measures of the excess pore pressure in dissipation tests of piezocone is presented. In cohesive soils, excess pore pressure and undrained shear strength are dependent on the same variables (stress state, stress history, soil stiffness), which allows them to be related by the theoretical cavity expansion-critical state framework. This paper mentions the mathematical formulation that supports the theoretical framework used, its relationship with the Nkt and NΔu factors and their estimation in a case studied. The results obtained are consistent within the dispersion found in the international literature and encourage the use of the method in engineering practice.
