METHOD OF EXCAVATION CONSTRUCTION

PURPOSE:To improve the efficiency of boring in building construction work, etc., by properly using an excavator excavating the soft ground by a cutter bit and an excavating device excavating a base rock, etc., by a roller cutter respectively and excavating a deep pit. CONSTITUTION:A cutter pit 2 for an excavator 6 is brought into contact with a ground surface, a cylindrical section 2 is rotated and driven, a soil section is cut, and soil remaining in the cylindrical section 2 is extracted to the outside by inserting a digging-out machine from an upper section while burying the excavator 6 in soil. Since excavation is brought to a difficult state when the pit is excavated continuously and reaches a base rock, etc., the excavator 6 is removed, an excavating device 10 is installed in place of the excavator 6, and a cylindrical section 12 is turned and driven. A cemented carbide tip is revolved while giving a shock to the base rock in a cutter body 15 for the roller cutter 11 of the cylindrical section 12 of the excavating device 10. The base rock is crushed, and the pit is excavated efficiently. Accordingly, the excavator 6 is used at, the time of a soil layer and the excavating device 10 at the time of the base rock, thus allowing correspondence even to both hard and soft beds.