The renovation was carried out to make Osaka Castle, symbol of
Osaka, more beautiful and solid. The Main Tower glittering with
gold was revived by making the most of advanced building technology
available at the time. |
High-tech
Construction to preserve the symbol of the city
As deterioration of the
restored Main Tower aggravated over the course of 60 years, a large-scale
renovation was undertaken from 1995 to 1997. It was carried out
with the basic principle of restoring the original appearance of
the castle before handing it over to the 21st century. The renovation
was done by making the most of the old parts while supplying new
materials.
The work needed high technology and high-leveled accuracy in execution.
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| Before the renovation |
After the renovation |
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Renovation
of the Exterior of the Main Tower
Renovation of Roof
Elaborate water-proofing work and the renewal of the copper roof
tiles were conducted. All gold-leaf eaves edge tiles (flat eaves
tiles and round eaves tiles) were renewed. About 55,000 copper roof
tiles (round and flat tiles) were first removed from the building.
Before they were re-installed, 80% of them were cleaned and repaired.
Re-applying Alkali Solution
A latest electrical and chemical
method, in which alkali solution is permeated into the interior
of concrete to prevent the corrosion of iron frames and reinforcement,
was applied. Durability of concrete was improved by applying a corrosion
protective covering. |
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After the iron scaffolding was removed, renovated Osaka Castle glittering
with gold could be seen. |
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Renovation
of Outer Walls and the Reserve Sides of the Eaves
The foundation of the outer walls were treated with Pinnet method
to prevent peeling off of the existing walls.
Renovation of Interior Fittings and Handrails
Renovation of Ornamental Fixtures
Bending down tigers and Shachi
(roof tile in the shape of a mythical ocean fish) ornamentation
of the Main Tower of Osaka Castle were first removed from the structure.
After being repaired, three layers of gold leaf were glued to them.
When they were re-assembled, the radiant brightness of gold ornamentation
was revived. |
Renovation
of the Interior of the Main Tower
Finishing of the Interior
The interior of each floor was renewed. With equal access for all
people taken into consideration, the flow of the visitors was re-designed.
Lighting of show cases was improved, and the facilities and its
functions were also improved, including extension of the internal elevator.
Reinforcement of the Structure
To increase earthquake resistance, on the supposition of a Level
2 earthquake (severe shock), new walls of earthquake-proof steel
plates were installed from the first to fourth floors, which became
the principal posts of the Tower and carbon fiber and reinforced
rods were coiled onto the pillars and beams for strenghening. |
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An elevator which allows wheelchair access to inside the Main Tower
was also installed. |
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