Construction method null of underground body

摘要

PURPOSE:To simplify the working processes during construction of an open caisson and increase the precision of construction, by providing a cut-off wall preventing underground water from penetrating into an underground concrete body, at the external periphery of the scope of the body. CONSTITUTION:A cut-off wall 2 like a continuous underground wall is constructed deeper than the depth of an underground oncrete body at the periphery of the expected area of the underground concrete body to prevent the underground water from penetrating into the construction site of an open caisson 1. And a plurality of deep wells 3 are excavated within the cut-off wall 2 to suck up the underground water within the cut-off wall 2 and lower the underground water level. In the mean time, the underground is excavated in the air to settle the open caisson 1 and construct the underground concrete body. Center hole jacks 41 are arranged near the cutter position 11 for settling of the open caisson 1 and the caisson 1 is safely and securely settled by making use of the tensile reaction of anchors 4a.