Remedy of Deep Soil Mixing Quality for Montmorillonite Clay Deposited in the Mekong and Mississippi Deltas

摘要

Wet type deep mixing (DM) columns have been installed in the southern region of Vietnam and in Louisiana, the United States, to increase the stability of slopes and mitigate ground settlement. Prior to DM production, laboratory mixing tests need to be executed carefully. Certain types of clay, such as Montmorillonite clay deposited in major river deltas in the South of Vietnam and in the Southern United States, are not easy to mix with cement in laboratory tests. Difficulties also arise in mixing on site. This paper describes the clay property and considers a case study of a laboratory mixing test and differences with Japanese clay mixing results. In addition, suitable admixtures to remedy the mixing quality for more difficult clays are introduced, without significantly increasing the cement volume.