Original Paper(Vol.61 No.1 pp.2-6)

History and Current State of Development of Vacuum Consolidation Method in Japan

Seiji SUWA, Masashi KAMON, Masaaki KIYAMA and Mitsuharu FUKUDA

Abstract:This paper shows the short history and the prospect in future on the development of the vacuum consolidation method in Japan. The vacuum consolidation method has the similar history of development of plastic board drain method. Both methods which are currently used for the soft ground improvement constitute of three phases of development. The first phase of the vacuum consolidation method is the introduction stage started in 1970s. But it was soon disappeared in the construction market without proved its efficiency. But after the stagnation of about 10 years was passed, the vacuum system revived to apply the road fill on the soft ground again. Because its superiority of acceleration of consolidation was recognized that is attained not considering failure of ground caused by fill as pre-loading. This paper reviews the development, stagnation and revival of this method focusing on why the vacuum consolidation method revived. It leads the current assessment and future perspective of the vacuum consolidation method.

Key Words:Vacuum consolidation method, Plastic board drain, Paper drain, History