BACKFILLING DEVICE OF DRILLING HOLE AND BACKFILLING METHOD OF DRILLING HOLE

To provide a technique capable of surely discharging bentonite into a drilling hole without leaving an organic impurity in the drilling hole and preventing the deterioration of the effective volume of a container.SOLUTION: A backfilling device of a drilling hole comprises: a cylindrical container which is filled with a filler that mainly contains pellet-like and/or block-like bentonite and has an ice film formed on at least a portion of the surface; and a conveyance unit which conveys the container filled with the filler to a prescribed position in the drilling hole. The container comprises: an ice plug part which has an ice plug that can temporarily block a discharge port formed on a lower end and a communication hole communicating the inside and the outside of a container; and a loading part which is provided right above the ice plug part and is loaded with a filler on the ice plug. The backfilling device discharges the filler to the outside from the inside of the container when the container is conveyed to the prescribed position in the drilling hole by the conveyance unit and the ice plug melts due to permeation of underground water in the drilling hole from the communication hole.SELECTED DRAWING: Figure 1 【課題】掘削孔内に有機質の不純物を残存させることなく、掘削孔内に確実にベントナイトを吐出できて掘削孔を閉塞可能であり、かつ、容器の有効容積が損なわれることがない技術を提供すること。【解決手段】ペレット状および／またはブロック状のベントナイトを主として含み且つ表面の少なくとも一部に氷の膜が形成された充填材が装填される筒状の容器と、充填材が装填された容器を掘削孔の内部の所定位置まで搬送する搬送部と、を備え、容器は、下端部に形成された吐出口及び容器の内部と外部を連通する連通孔を一時的に閉塞可能なアイスプラグを有するアイスプラグ部と、アイスプラグ部の直上に設けられアイスプラグ上に充填剤が装填される装填部と、を有し、容器が搬送部により掘削孔内の所定位置まで搬送されることにより、掘削孔内の地下水が連通孔から浸入してアイスプラグが解け、充填材を容器の内部から外部に吐出する、掘削孔の埋め戻し装置。【選択図】図１