About TTK

Constructing high-rise buildings
in earthquake-prone Japan

Nowadays, high-rise buildings and condominiums are being constructed in great numbers in Japan’s urban areas.
How is it possible for high-rise buildings to be constructed in an earthquake-prone country like Japan?
One reason is the use of reinforced concrete, which provides excellent seismic resistance and durability.

Advanced reinforced concrete provides the support for high-rise buildings

Reinforced concrete is a construction material that combines the advantages of concrete, which resists compression well, and reinforcing bars, which resist tensile and bending forces well. Reinforced concrete has contributed greatly to the development of modern high-rise architecture, with its excellent seismic resistance and durability. 


To meet the market demand for ever higher structures, products designed to increase the strength of concrete and rebars are currently being developed. The evolution of reinforced concrete is one reason why high-rise buildings and condominiums can be constructed in Japan, a country that is frequently hit by earthquakes.

The number of high-rise office buildings and condominiums is expected to further increase, and TTK is a leading manufacturer of the high-strength rebars used to support such structures.

How TTK's rebars are manufactured

How, then, are high-strength rebars—which are indispensable in the construction of high-rise buildings—manufactured?

The raw material for rebars is scrap iron collected from demolition sites and factories. This waste material is recycled and transformed into high-quality rebars as follows: (1) the scrap iron is melted in an electric furnace; (2) auxiliary materials are added to adjust its chemical composition; and (3) it is cast into billets and rolled. Given this, our steel business is, in effect, also a recycling business that allows us to contribute to the realization of a sustainable society.

Production lines with state-of-the-art technologies are indispensable for the manufacture of high-quality rebars. Equally important, of course, is the capability to operate these production lines and manage product quality effectively. Making every effort to develop and manufacture high-strength rebars that far exceed Japanese Industrial Standards (JIS), TTK leads the industry with its advanced manufacturing technologies.