SOIL DRAINAGE DEVICE

To provide a soil drainage device capable of simultaneously carrying out work for depositing soil to be treated and work for forcibly sucking and discharging gap water from the soil to be treated efficiently with a simple structure.SOLUTION: The soil drainage device comprises: a catchment facility for catching gap water from soil to be treated; and a negative pressure application facility for applying negative pressure on the soil via the catchment facility. The catchment facility comprises a water permeable mat laid on the foundation with a lower surface and a peripheral edge closed and with the soil deposited on an upper surface, and a horizontal drain material buried in the water permeable mat. The negative pressure application facility comprises a water storage tank for storing the gap water, a drainage device that discharges the gap water stored in the water storage tank, and a pressure reduction device that reduces pressure in the water storage tank. The water storage tank and the horizontal drain material are communicated with each other through a connection tube.SELECTED DRAWING: Figure 1 【課題】簡略な構成で効率よく、処理対象土を堆積させる作業と、処理対象土から間隙水を強制的に吸引し排出する作業を、並行して行うことの可能な、土壌排水装置を提供する。【解決手段】処理対象土の間隙水を集水する集水設備と、集水設備を介して処理対象土に負圧を作用させる負圧作用設備と、を備える土壌排水装置であって、集水設備が、地盤上に敷設されるとともに下面及び周縁部が閉塞され、上面に処理対象土が堆積される透水マットと、透水マットに埋設される水平ドレーン材と、を備え、負圧作用設備が、間隙水を貯留する貯水槽と、貯水槽に貯留した間隙水を排水する排水装置と、貯水槽内を減圧する減圧装置と、を備え、貯水槽と水平ドレーン材とが、連結管を介して連通されている。【選択図】図１