Engineering geological characterization of the soils in Mochudi North East.

This study tries to investigate the engineering behavior of the soils which is one of the important parameter in any civil construction. The purpose of this study is to assess the engineering geological properties and characterize soil of North-East part of Mochudi village located in the South Eastern part of Botswana in Kgatleng district. More over the ultimate aim is to also produce an engineering geological map of the area. The study area is about 19 square kilometers and on the periphery of the village. This site was carefully chosen for the reason that the village is expanding towards that side so more construction is taking place. 

The engineering geological conditions of the soil were determined both in the field and in the laboratory. Twelve one cubic meter pits were drilled and 26 samples were collected from them taking into account the soil profile in the pit. The samples were analyzed in the engineering geology laboratory of the Department of Geology of the University of Botswana. The unified Soil Classification System was used to classify the soils. From field analysis, these soils displayed diverse colors such as light brown, brown, grey and reddish brown. Result of laboratory dry sieve analysis of the soils showed various proportions of coarse (sand) and fine (clay and silts) sizes. Sand size particles range between 92.92-95.38% whiles fines are between 4.82-7.08% across all samples which confirm poor grading. The plasticity index is between 0 and 17% among three samples whereas others were Non-plastic and very slightly plastic. According to the Unified Soil Classification System, three types of soils were identified: poorly graded sand, poorly graded sand with silty clay and poorly graded sand with silt. . These results of the study would advantage the people whom are to construct new residential houses to make extra informed decisions, planning and design. However it has been found out that people who are constructing houses in the area have no idea about the importance of engineering behavior of the soil. The results from this study can also be used as a source of data for further studies to be done in the area.