OREANDA-NEWS. Nippon Steel & Sumitomo Metal Corporation (NSSMC)'s ultra high strength 1,000-N grade steel for building structures (Product Name: BT-HT880) has been adopted at the "Open Labo-2 "experimental facility at the Technical Research Institute of Obayashi Corporation (Obayashi).

1,000-N grade steel is the world's strongest ultra high strength steel for building structures that was developed to improve the earthquake resistance of buildings and has approximately 2.7 times the yield strength of conventional 490-N grade steel. Amid requirements for larger-scale and taller buildings, the use of 1,000-N grade steel is expected to reduce the quantity of steel used and transportation costs thanks to thinner and lighter steel materials while also shortening processing time at plants and work periods for on-site construction due to a reduction in welding locations and welding volume.

It will also be possible to reduce the number of columns in building structures and make them thinner, which will result in large span spaces that combine good design and amenity. Furthermore, owing to the ability to develop structures in which seismic energy dissipation mechanisms absorb the majority of energy while 1,000-N grade steel columns shake elastically, due to combination with energy dissipation mechanisms such as dampers, high earthquake resistance required in business continuity plans (BCPs) will be realized.

On this occasion, NSSMC's 1,000-N grade steel was used for the column material of "Open Labo-2", which Obayashi, a leader in Japan's construction industry, constructed by concentrating leading-edge technologies, and a construction method employing welded 4-sided box column, which is generally used for high-rise buildings as the columns, was adopted to make maximum use of the strength of 1,000-N grade steel. This is the second case where 1,000-N grade steel has been adopted since the No. 1 Building of NSSMC's Amagasaki R&D Center, which was completed in 2011. NSSMC will continue to contribute to building national resilience as well, including the development of social infrastructure, through the application to structures of ultra high strength steel for building structures.

NSSMC plans to announce this development at the Fiscal 2014 Annual Convention of the Architectural Institute of Japan.