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RESUMO: Neste trabalho é realizada uma análise computacional por meio da resolução de equações diferenciais para a modelagem de soluções analíticas e numéricas (MDF) do comportamento mecânico de um maciço rochoso contendo descontinuidades. Realizou-se simulações adotando um bloco composto por um material homogêneo, isotrópico e linear elástico sob atuação de uma força externa compressiva aplicada na sua extremidade livre e confinado entre duas descontinuidades rígidas, nas superfícies inferior e superior. A descontinuidade inferior apresenta rugosidade, caracterizada por um módulo de rigidez ao cisalhamento que conduz a uma distribuição de tensão cisalhante e a um deslocamento relativo entre o bloco e a base. Os resultados foram gerados através da compilação dos dados no programa computacional FORTRAN 90, e, com isso, pode-se verificar o deslocamento relativo entre o bloco e a descontinuidade, bem como as tensões atuantes em cada ponto previamente definido; e ainda realizar uma comparação entre as soluções analítica e numérica. Como principal contribuição do trabalho para a área da geotecnia, cita-se a possibilidade de uma análise de deslocamento de descontinuidades presentes em maciços rochosos mais próxima da realidade já que considera o meio como descontínuo. Além disso apresenta-se uma solução computacional de fácil implementação e entendimento.ABSTRACT: In this work a computational analysis is performed by solving differential equations for the modeling of numerical (MDF) and analytical solutions of the mechanical behavior of a rock mass with discontinuities. Simulations were carried out by adopting a block composed of a homogeneous, isotropic and linear elastic material under the action of an external compressive force applied at its free end and confined between two rigid discontinuities on the lower and upper surfaces. The lower discontinuity presents roughness characterized by a shear stiffness modulus leading to a shear stress distribution and a relative displacement between the block and the base. The results were generated through the compilation of the data in the FORTRAN 90 computer program, and with this, it is possible to verify the relative displacement between the block and the discontinuity, as well as the shear stresses acting at each previously defined point; and also perform a comparison between analytical and numerical solutions. The main contribution of the work to the area of geotechnics is the possibility of an analysis of discontinuity displacement present in rock mass closer to reality since it considers the environment as discontinuous. In addition, a computational solution is presented that is easy to implement and understand.

In this study, a ground anchored wall located in Belo Horizonte containing 295 anchorages in a sandy silt soil was analyzed. The load capacity of all the anchors was calculated by extrapolation of the receipt tests by the Van der Veen method through the CsAGeo web application. The shear strength in the soil-anchor interface was obtained from a semi-empirical method. Two criteria to analyze the extrapolated curves of Van der Veen were used. In the first criteria, the shear strengths of all the extrapolated curves were calculated. In the second criteria, only those curves from the extrapolations considered as reliable were used to calculate the shear strengths. The main objective of this work is to set up the value of shear strength at the soil-anchor interface through extrapolation of the mathematical and semi-empirical methods. The semi-empirical method was carried out in soil and executive methodology equal to the work analysed, which increases the accuracy of these values contributing to containments using anchors. The results were grouped according to the ranges of the penetration resistance (N SPT). An increasing tendency was identified in the shear strength as the value of the resistance to penetration increased. In addition, the linear tendency was observed for the reliable curves.