This paper reports and evaluates the subsurface investigations of lateritic soil in Muglad Basin. Lateritic soil is described as highly weathered and altered residual/transported soil formed by the in-situ weathering ...This paper reports and evaluates the subsurface investigations of lateritic soil in Muglad Basin. Lateritic soil is described as highly weathered and altered residual/transported soil formed by the in-situ weathering and/or decomposition of rocks in the tropical and sub-tropical regions with hot, humid climatic conditions. The field works include excavation of test pits, drilling of boreholes and performing of SRT (standard penetration test). The engineering properties of soil such as sieve analysis, consistency, compaction test, CBR (California bearing ratio) test are deduced in the laboratory. Lateritic soil is also evaluated to be used as foundation and construction materials. Concretionary lateritic soil is valuable road pavement materials, widely used in the tropics as sub-base, base material and for gravel roads. The term laterite, however, has tended to be indiscriminately applied in tropical highway engineering to any red soil. Lateritic soils in this study area were classified as reddish brown, medium dense to very dense, clayey silty sand with noodles of quartz and gravels. According to laboratory test, the lateritic soil was found to be good as construction materials, and can be used for embankment purposes; on the other hand, blending such materials with gravels can improve the low CBR values.展开更多
This paper evaluate subsoil corrosivity using the electrical resistivity method which was carried out to determine the subsoil resistivity and estimate the degree of corrosion, the resistivity measurements were conduc...This paper evaluate subsoil corrosivity using the electrical resistivity method which was carried out to determine the subsoil resistivity and estimate the degree of corrosion, the resistivity measurements were conducted by using SAS300c resistivity meter. This involves applying a voltage into the soil through metal electrode and measuring the resistance to the flow of electric current. An AC-power supplies current flow (I) between two outer electrodes and the resultant voltage different (V) between two inner electrodes is measured using the Wenner Arrangement. The soil resistance given by R = V/I. This needs to be standardized over a unit length, the resistivity p which measured in ohm-m the equation is, ρ= 2ДdR. There are many factors control the ground resistivity such as soil composition, moisture content, pore water chemistry and pH. The results of the survey show inverse proportion between corrosivity and electrical resistivity, therefore resistivity method is very useful to incipient the corrosion as well as effective, quick, reliable and economic method. Structures such as natural gas, crude oil pipelines and steel constructions were reported to have been affected by soil corrosion all around the world, it can be concluded that sub soil corrosivity around the study area increases southwestern ward with depth.展开更多
文摘This paper reports and evaluates the subsurface investigations of lateritic soil in Muglad Basin. Lateritic soil is described as highly weathered and altered residual/transported soil formed by the in-situ weathering and/or decomposition of rocks in the tropical and sub-tropical regions with hot, humid climatic conditions. The field works include excavation of test pits, drilling of boreholes and performing of SRT (standard penetration test). The engineering properties of soil such as sieve analysis, consistency, compaction test, CBR (California bearing ratio) test are deduced in the laboratory. Lateritic soil is also evaluated to be used as foundation and construction materials. Concretionary lateritic soil is valuable road pavement materials, widely used in the tropics as sub-base, base material and for gravel roads. The term laterite, however, has tended to be indiscriminately applied in tropical highway engineering to any red soil. Lateritic soils in this study area were classified as reddish brown, medium dense to very dense, clayey silty sand with noodles of quartz and gravels. According to laboratory test, the lateritic soil was found to be good as construction materials, and can be used for embankment purposes; on the other hand, blending such materials with gravels can improve the low CBR values.
文摘This paper evaluate subsoil corrosivity using the electrical resistivity method which was carried out to determine the subsoil resistivity and estimate the degree of corrosion, the resistivity measurements were conducted by using SAS300c resistivity meter. This involves applying a voltage into the soil through metal electrode and measuring the resistance to the flow of electric current. An AC-power supplies current flow (I) between two outer electrodes and the resultant voltage different (V) between two inner electrodes is measured using the Wenner Arrangement. The soil resistance given by R = V/I. This needs to be standardized over a unit length, the resistivity p which measured in ohm-m the equation is, ρ= 2ДdR. There are many factors control the ground resistivity such as soil composition, moisture content, pore water chemistry and pH. The results of the survey show inverse proportion between corrosivity and electrical resistivity, therefore resistivity method is very useful to incipient the corrosion as well as effective, quick, reliable and economic method. Structures such as natural gas, crude oil pipelines and steel constructions were reported to have been affected by soil corrosion all around the world, it can be concluded that sub soil corrosivity around the study area increases southwestern ward with depth.