Monitoring the strength properties of electrokinetically treated soil by bender elements to determine the treatment period

• Main Authors: Colin Hunter, Eltayeb Mohamedelhassan, Ayan Sadhu
• Format: Article
• Language: English
• Published: Elsevier 2021-06-01
• Series: Soils and Foundations
• Subjects: Bender elements; Non-destructive testing; Electrokinetics; Pile model; Sandy clay
• Online Access: http://www.sciencedirect.com/science/article/pii/S0038080621000329

Bender elements have been used as a non-destructive soil investigation technique by many researchers and have proven to be effective in predicting the shear strength of various soils. In this paper, electrokinetic treatment tests were performed with embedded bender elements to monitor the increase in the shear strength of a soft sandy clay during the treatment. The bender element system, designed and assembled for this study, was integrated into the electrokinetic treatment process in order to quell a common uncertainty associated with this form of soil improvement technique, namely: when is the treatment completed? The cross-correlation and first-peak arrival times were used to measure the shear wave velocity of a clayey soil under the treatment of electrokinetics using bender elements. To determine shear wave velocity before and during treatment, a variety of shear wave tests were performed every hour of treatment using frequencies ranging from 100 Hz to 2500 Hz via the use of bender element. The results show that monitoring the soil improvement during the treatment by bender elements can shorten the treatment time by 43% and reduce the energy consumption, which is a major expenditure in an electrokinetic treatment process, by 33% while consistently improving the shear strength and the load capacity by approximately 200% and 300%, respectively.