Soil resistivity measurements to predict moisture content and density in loose and dense soil

摘要

In the past, most of the soil electrical resistivity charts were- developed based on stand-alonegeomaterial classification with minimal contribution to its relationship to some of geotechnicalparameters. Furthermore, the values cited a very wide range of resistivity with sometimes overlappingvalues and having little significance to specific soil condition. As a result, it created some ambiguitiesduring the interpretation of observations which were traditionally based an qualitative anomalyjudgments of experts and experienced people. Hence, this study presents soil resistivity values basedon laboratory experiment with a view to predict the soil moisture content and density in loose anddense soils. This study used a soil box and a resistivity meter to test a clayey silt sail, increasing itswater usage from 1-3% based on 1500 gram of dry soil. All the moisture contents and density datawere observed concurrently with 25 electrical soil resistance observations being made on the soil Alltesting and formula used were In accordance with that specified in BS1377 (1990). It was apparentthat the soil resistivity value was different under loose (L) and compact(C) condition with moisturecontent (w) and density (pbulk) correlations being established as follows; pbulk(C)=2.5991p-0.037, pbulk (L)=-0.111 ln(p) + 1.7605, W(L)=109.98p-0.286, and W(C)=121.88p-0.363 with determinationcoefficients, R2 that ranged between 0.69 - 0.89. This research therefore contributes a means ofpredicting these geotechnical parameters by related persons such as geophysicist, engineers andgeologist who use these resistivity techniques in ground exploration.