GEOTECHNICAL AND RADIOMETRIC STUDIES FOR EL-HAMRAWEIN AREA- EASTERN DESERT- EGYPT

Abstract

This research involves geotechnical and radiometric studies for El-Hamrawein area- Eastern Desert- Egypt. The studied area is mainly composed of gravely sands enriched soil cover the rock with large thickness. Laboratory tests were performed on representative soil and rock samples to determine their physical, mechanical and chemical characteristics such as: grain size distribution, specific gravity, moisture content, bulk density, shear box, bearing capacity, unconfined compressive strength, chemical analysis, uranium and thorium concentrations of rocks and soils. One hundred and eight samples were collected from 16 boreholes and classified into 24 rock sample and 84 friable sand and gravel, have been taken at a depth from 1 to 15 m. Uniformity coefficient (Cu) value ranges from (4.55mm) to (7.91mm) and curvature coefficient (Cc) value ranges from (1.98mm) to (0.70mm). The studied samples in this study are classified as well-graded soil from the point of view of classification engineering geology. Specific gravity values range from 2.47 to 2.70. The geotechnical studies include direct shear test, where effective friction angle (ϕ) range from 36o to 37o and bearing capacity of soil are ranging from (1901 KN/m2 to 2059 KN/m2). Radiometric studies including gammaray logging and quantitative uranium and thorium analyses were carried out in order to give an idea about the distribution of uranium and thorium in the study area. Uranium ranges from 1.8ppm to 2ppm, thorium range from 3.6ppm to 4.2ppm at different depths from 0 to 5m. These values indicate that the area has safe radiation .