JP2936365B

PURPOSE:To require no strut for landslide protection, no other temporary work and no temporary cost, to curtail a construction period, to reduce a construction cost, to make it possible to excavate the ground by an automatic excavator and to promote the environment of a working place (specially steps) with an all weather type for a skeleton construction method similar to an inverted construction method used for the construction of an underground structure skeleton of a building. CONSTITUTION:Structural stuts 2 are constructed, and after a primary excavation of the ground 1, a first floor 3 is constructed on the ground level. A secondary excavation of the ground 1 is made, a first driving floor 4 as the lowest floor is constructed, and a second driving floor 6 is constructed on a jack device 5. A third excavation of the ground 1 is made, the first and the second driving floor 6 are lowered, a basement first floor 7 is constructed on the second driving floor 6. The driving floors 4 and 6 are lowered, the basement first floor 7 is set as a permanent floor.