Nitto Chemical Industry Co., Ltd.

Yamaguchi Kikai Kogyo Co., Ltd.

Nihon Sogo-bosui Co., Ltd.

Nihon Soil Engineering Co., Ltd.

Mitsuji Ishida

Kenji Takeuchi

Takashi Miki

Shunsuke Tazawa

Katsuhiko Kurihara

Mineo Murata

Akiyoshi Horiba

Tomohiro Sakurada

Syouichi Kashima

Goro Murai

A method of improving water retention characteristics of soil by using water absorption polymer, including the steps of forming a water impermeable layer in a subsurface layer of the ground, and providing a water absorption polymer layer in an upper region of the water impermeable layer. The method is executed by an apparatus for forming a water impermeable layer in a subsurface layer of the ground, the apparatus also being used to mix water absorption polymer in the soil in an upper region of the water impermeable layer, by an injecting apparatus having a drilling function.

Method of improving ground and apparatus used therefor

An improved grout impregnation method which uses an injection tube for contacting and mixing different kinds of materials supplied thereinto separately to prepare a grout and impregnates the grout into the earth through an injecting opening provided at a tip end of the tube. In this method, a first pressure-holding valve is provided within a higher-pressure path for one of the materials which is supplied under a higher pressure, a mixing section is provided downstream the first pressure-holding valve but in the vicinity thereof for contacting and mixing said one of the materials with another one which is supplied under a lower pressure, and a second pressure-holding valve is provided downstream the mixing section; said one of the materials is passed through the first pressure-holding valve, which reduces the pressure of said one of the materials, and then contacted and mixed with said another one at the mixing section; the contacting and mixing is carried out under a pressure exceeding an atmospheric pressure and determined by the second pressure-holding valve; and the grout resulting from the contacting and mixing and passing through the second pressure-holding valve is impregnated into the earth through the injection opening.

Grout impregnation method

Growing community of inventors

Yokohama, Japan

Mitsuji Ishida