Civil Engineering Association

Overview
Gate Tower Building is a 16-story office building in Fukushima-ku, Osaka, Japan. And what makes it notable is the highway that passes through the 5th-7th floors of this building.

The building has a double core construction, with a circular cross section. The Umeda Exit of the Ikeda Route of the Hanshin Expressway system (when exiting the highway from the direction of Ikeda) passes through the fifth through seventh floors of this building. The highway is the tenant of those floors. The elevator passes through the floors without stopping, floor 4 being followed by floor 8. The floors through which the highway passes consist of elevators, stairways and machinery. The highway does not make contact with the building. It passes through as a bridge, held up by supports next to the building. The highway is surrounded by a structure to protect the building from noise and vibration. The roof has a heliport.

The building has a double core construction, with a circular section and special care is taken by providing surrounded structure to the highway to protect the building from noise and vibration.

Motive
“Wood and charcoal industry” held the property rights for this plot of land since the early Meiji period, but the gradual move to other sources of fuel resulted in those company buildings deteriorating. In 1983, the redevelopment of this area was decided upon, but building permits were refused because the highway was already being planned to be built over this land. The property rights' holders refused to give up, and negotiated with the “Hanshin Expressway Corporation” for approximately 5 years to reach the current solution.
Although normally highway corporations purchase the land they build a highway on or over, it is not guaranteed to succeed and therefore issues like this can arise.
For that reason, the highway laws, city planning laws, city redevelopment laws and building codes were partly revised in 1989 to permit a so-called Multi-Level Road System that allows the unified development of highways and buildings in the same space. This system was originally designed to facilitate the construction of the second Ring Road in the vicinity of Toranomon, Minato-ku, Tokyo, but in the end was not applied there. Instead, the system was put into effect in the construction of the Gate Tower Building, becoming Japan's first building to have a highway pass through it. Normally highways are still built underground in these cases, and passing through a building is an extremely rare occurrence.