Method of Unsaturation Soil by Air Injection (Air-des Method)
Method of Unsaturating Soil by Air Injection is a liquefaction countermeasure technique by injecting air into a liquefiable deposit. This method is focused on obtaining higher liquefaction strength by slightly de-watering sand. The term 'air desaturation' is abbreviated 'Air-des'. It means that the ground is desaturated by removing water in voids between soil particles by injecting air into the ground.
We started developing the Air-des liquefaction countermeasure technique in 1996 with the late Dr. Shunta Shiraishi. Since 2008, we have been jointly developing the method with the Shikoku Regional Development Bureau of the Ministry of Land, Infrastructure, Transport and Tourism ; Ehime University; Toa Corporation; Fudo Tetra Corporation; and DIA Consultants Co., Ltd. This effort includes conducting on-site demonstration experiments to promote practical application of this new Air-des liquefaction countermeasure technique. In 2011, the Application Manual of the Air-des Method was completed after evaluation by the committee of the Coastal Development Institute of Technology.
Outline of Air-des method
Features
- This method costs less than other liquefaction countermeasure methods because it uses air.
- This method reduces the environmental load during application also because it uses air.
- This method can be applied in narrow spaces because the needed facility is small.
- This method can be applied under a building structure while the building remains in use.
This method is being studied and developed further to be a feasible method while resolving the remaining technical issues.
