Etude pétrographique et géotechnique des granites de Tissalatine et leurs arènes

Abstract

This work will focus on the granites of Tissalatine region, located 10km northwest of the City of Djanet. This region is characterized by the presence of two types of granites: Pharusian granites and post-tectonic granites. The granitic sand is the product of weathering of granite, exposed to surface conditions by temperature, water and wind, will transform the mica and feldspar in the clay particles. This work is to determine the petrographic, granulometric and geotechnical characteristics of granitic materials and draw conclusions about their utility for purposes of development of basis infrastructure (roads, runways and terminals). Petrographic analysis showed that the granite is studied type granite with large crystals of plagioclase light-colored, pinkish, with a mineral composition of 30% quartz, 15% biotite, 20% feldspar, 30% plagioclase and 5% other minerals. The granitic sand is graded according to the analysis in the geotechnical category (B), family of sandy or gravelly soils with the presence of fines, with compaction characteristics and resistance to compression acceptable. From a geotechnical stand point, these materials are favorable for the realization of the layers of fill (embankments), layers and layers of foundation bases. According to the results of granulometric granites, the Micro-Deval and Los Angeles test, the use of these aggregates in road infrastructure are favorable.