An Investigation into Some of the Engineering and Index Properties of Soils Found Nearby Lake Abaya of Ethiopia

An onshore construction near to lake is typical for recreational area, to accommodate Guests, tourists, and local visitors. Therefore constructions are required for lodges, hotels and related functions to host visitors. Which towns are abundant with natural gifts like lake have the possibility to expand toward the lake in their development plan. Arba Minch city is one of the cities rapidly growing in Southern part of Ethiopia, which has two naturally gifted Lake Chamo and Lake Abaya which are separated by God’s natural bridge. For all constructions near to the lakes, it is necessary to identify the engineering and index properties of the subsoil since they are required as design data for foundations, retaining wall and related structures. Thus, the purpose of this study is to investigate engineering and index properties of the soil nearby the Lake Abaya. During the investigation has been started by preliminary site observations to locate the test pit points, then around 13 test pits are systematically defined, and about 20 representatives disturbed soil samples are collected from various depths. Along with sample collection in - situ density test are conducted at respective depth. Laboratory tests are held on the soil samples to obtain engineering and index properties of the soil deposit. The type of tests is selected depending upon the type of soil and conducted according to ASTM soil testing standard. For the study area field density, natural moisture content and specific gravity value range from 1.58 to 1.86 gm/cc, 17.5 to 41.8 % and 2.66 to 2.74, respectively. The optimum moisture content of soil and maximum dry density value range from 16.5 to 25.9 % and 1.31 to 1.67 gm/cc respectively. The amount of gravel, sand, silt, and clay in the soil mass ranges from 0% to 4.16 %, 2.75% to 34.08 %, 23.53% to 61.31 % and 17.39% to 62.95 % respectively. The soils in the study area are grouped under SM, CH, CL and ML soil group based on USCS. Shear strength parameters like cohesion, undrained shear strength and angle of internal friction values range from 0Kpa to 7Kpa, 49Kpa to 127Kpa and 250 to 330 respectively. The coefficient of consolidation and recompression index values range from 0.3 to 0.41 and 0.03 to 0.05 respectively. Generally, soil SM soil has the functional bearing capacity, whereas ML, CL and CH soils have the weak bearing capacity. Therefore, the soil deposit in the area shall be overlaid by suitable selected soil materials and well compacted before the foundation of the structures would be placed