Estimation of Fine Fraction Content in Soil by Electrical Resistivity

Wedish Weight Sounding test is widely used as a research method to evaluate the residential sites. Advantage of Swedish Weight Sounding test is the ability to evaluate the bearing capacity of residential sites. On the other hand, a disadvantage of Swedish Weight Sounding test is inability to determine the soil and groundwater level. The determination of the soil is based on the experience of the operator. Information obtained from the results of the Swedish Weight Sounding test is insufficient to evaluate the residential ground. Suppose that if it is possible to incorporate the determination method of the soil by electrical resistivity using Swedish Weight Sounding test holes, a lot of information will be gained. As an ideal way, the electrical logging method by the electrode to the Swedish Weight Sounding test hole is effective. The purpose of this study is intended to clearly determine the classification of soil due to electrical logging method by Swedish Weight Sounding test hole. The experiment is divided into in-situ and laboratory experiments. However, the result of laboratory experiments is not clear whether the results can be applied to the measurement of electrical resistivity in natural ground. To establish a method of electrical logging using Swedish Weight Sounding test hole, a ground survey will have been done to determine the ground liquefaction of residential sites. As a basic research, the authors attempted to clarify the evaluation method of soil fine fraction content by using the electrical resistivity using a sample soil of 57 types of laboratory experiments. In this experiment, portable electric conductivity meter was used in laboratory experiment. From the laboratory test, a formula to estimate the fine fraction content of soil was proposed. Further, as situ testing, an SWS test was conducted. After SWS test hole was filled with various kinds of KCL solution, electrical resistivity was measured. As a result, it was found that the formula on the fine fraction content of soil was useful in the field.