Geomechanical Characterization of Sandstones Cliffs of Segou (Senegal, West Africa) in the Madina Kouta Basin

Déthié Sarr, Meissa Fall, Papa Malick Ngom, Mapathé Ndiaye, Cheikh H. Kane, Makhaly Ba

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Laboratoire de Mécanique et Modélisation-UFR Sciences de l’Ingénieur, Université de Thiès, Thiès, Sénégal.

DOI: 10.4236/ijg.2012.31018                

Abstract

This work presents the behavior of Segou sandstones in the laboratory and in the field conditions. Four types of sandstone are collected in the northern part of the Madina Kouta basin (eastern Senegal). These types of specimens are the white sandstones, the red sandstones, the purple sandstones and the sandstones with intercalation of pelites. Uniaxial tests are carried out on these specimens of sandstones. The Young Moduli (E) and the Uniaxial Compression Strengths (Rc) are higher for the white sandstone. Values of the mechanical parameters decrease slightly for red sandstones due to an increase of the amount of pelites in the composition of the rock. Decrease of mechanical parameters is more important for the purple facies due to an important network of fractures. The facies with weaker characteristics corresponds to the sandstones with intercalation of pelites. This is due to the soft nature of the pelites. The slope stability of the Cliff sides depends also on to these characteristics.

Keywords

Unconfined Compression Test-Uniaxial Compression Strength (UCT, Rc);JRC (Joint Roughness Coefficient), Young Modulus (E); Roughness; Segou-Madina Kouta Basin; Discontinuities; Dihedral; Slope; Cliff

Conflicts of Interest

The authors declare no conflicts of interest.

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