Electrokinetic improvement of soft clay using electrical vertical drains

摘要

The performance of electrical vertical drains (EVDs) is investigated using laboratoryntests and a field test. The electrokinetic treatment generates an increase in the soil undrained shearnstrength of a natural clay soil from London, Ontario, from 3 kPa to over 100 kPa in the laboratory.nThe soil undrained shear strength in a field test conducted in marine clay increases from betweenn5 kPa and 13 kPa to between 22 kPa and 39 kPa on average after only five days of electrokineticntreatment using EVDs. It is observed in laboratory and field tests that the water flow generated bynelectro-osmosis stops shortly after the application of the electric current. The significant shearnstrength gains of soils observed in the laboratory and field tests are attributed to the reduction ofnsoil water content and increases in Atterberg limits which result from electrochemical reactions.