Soil Compaction Characterizations through Electrical Resistivity in Field Investigations

摘要

This paper presents soil compaction characterizations in field using soil electrical resistivity. In roads and highway engineering, it is necessary to achieve the expected dry density of soil through field and laboratory tests. Conventional tests include the standard procedures like sand cone method, rubber balloon method and nuclear method are normally conducted at sites as compaction work is progressing. To achieve field dry density of 90 to 95 % of maximum dry density the samples are determined from standard proctor tests in laboratory. Conventional methods are costly and tedious when large number of soil samples are to be collected from field for tests. Measurements of moisture contents are obtained by drying process of moist soil excavated from sites. Soil resistivity method is used in this research to obtain soil dry density, particle size distributions and soil compaction characteristics in field investigations. High precision digital multimeter, Fluke 8846A and insulation tester, KEW 3111V are used to measure soil electric resistivity of compacted soils. Results of standard proctor tests for maximum dry density in laboratory are compared with the performance of field compaction characterizations using electrical resistivity. The main advantage of using soil resistivity method and computer database programming is the acquisition of immediate and hence reliable results where field tests data is consequently characterized using information stored in a computer database. Soil compaction characterizations using resistivity method show good agreement with conventional method of soil investigations conducted in geotechnical laboratory of Universiti Kebangsaan Malaysia (UKM).