To reach 300m

MISSION3: Construction of deep underground space

To create a 300-meter-high vertical city, a large underground space is necessary to accommodate car parks and machine rooms.
Also, because Abeno Harukas was a construction project involving floors penetrating 30 meters below the surface and surrounded by a total of five rail lines (Kintetsu South Osaka line, Tanimachi and Midosuji subway lines, Hankai Uemachi line, and JR), it was critical to carry out safe construction at a considerable depth.

 Construction of deep underground space
Solution1: Inverted construction method

To excavate down to 30 meters below the surface in a safe manner taking the surrounding environment into consideration, the inverted construction method was used and the building’s floor levels were constructed downward from the first floor. In the inverted construction method, the surrounding retaining walls are supported by the floors constructed from the first floor in order to ensure safe excavation. Also, since upper and lower floors may be constructed at the same time, the construction period may be shortened.

Inverted construction method STEP1 Inverted construction method
Inverted construction method STEP2
Inverted construction method STEP3
Solution2: Takenaka soilcement continuous wall construction method (technical certification obtained)

The Takenaka soilcement continuous wall construction method was used to safely excavate 30 meters underground with various buildings surrounding the site. Since this method involves the reuse of excavated soil, construction byproducts are substantially reduced, which contributes to lowering the environmental burden.

 Takenaka soilcement continuous wall construction method