CONSTRUCTION TECHNIQUE OF CONTINUOUS UNDERGROUND WALL

PURPOSE:To construct a continuous underground wall by efficiently forming a drilled ditch for a bottom spread section for forming the bottom spread section to a part of the underground wall with excellent dimensional accuracy at the determined position of the bottom of a vertical drilled ditch in the construction of the continuous underground wall. CONSTITUTION:A vertically drilled ditch 6 in specified depth is excavated by using one excavator 2, and a guide member 7 for excavating a bottom spread section is disposed into the vertically drilled ditch 6. The excavator 2 drilling the vertically drilled ditch 6 is used as it is, and bottom-spread section drilled ditches 8, 10 are drilled continued to the bottom of the vertically drilled ditch 6 along the guide member 7. Accordingly, the bottom-spread section drilled ditches 8, 10 can be drilled with excellent dimensional accuracy at determined positions while improving excavation work, thus properly constructing a continuous underground wall.