Name: Kei Nakagawa

Position: Senior Researcher, Manager                                                                                                               KeiNakagawa高级工程师

Affiliation: JFE Steel Corporation, Steel Research Laboratory,                                                                                      

Civil Engineering Research Department

Brief personal history:

Mar. 2000, Graduated Waseda Univ., Faculty of Science and Engineering

Mar. 2002, Completed Waseda Univ., master’s course of Graduate School of Science and

Engineering

Apr. 2002 - Mar. 2003, NKK corporation

Apr. 2003 - Mar. 2009, JFE R&D Corporation

Apr. 2009 - JFE Steel Corporation

From 2002, in charge of development of building materials:

Cold-press-formed square steel pipes (TS 490 - 590MPa class)

Cold-roll-formed square steel pipes (TS 400MPa class)

High Strength Steel Plates           (TS 550 - 780MPa class)

Abstract: High strength steel (HSS) and Concrete Filled Steel Tube (CFST) are commonly usedin high-rise buildings in Japan since they have some advantages.

HSS enables to micrify cross-sectional size and reduce plate thickness of structural members,which leads to reduce delivery cost and welding work. So far in Japan's building practice, TensileStrength (TS) 550MPa class steel, which is similar to S460M in EN10025-4, is mostly used asHSS for high-rise buildings due to its cost-efficiency. JFE developed the 550MPa class steelplates for building structures for the first time in the industry. It secures both good weldabilityand seismic-resistance by applying advanced TMCP (Thermo Mechanical Control Process)technology.

On the other hand, CFST has advantages in ductile structural behavior and good fire-resistancecompared to empty steel pipe. JFE has been studied CFST in response to the demand in high-risebuildings, and has some experimental studies on CFST using TS 550MPa steel as a pioneer.In this presentation, firstly, the advantages of TMCP-type HSS are introduced in terms of thecharacteristics and design case study. Then, the advantages of CFST are outlined with someexperimental studies.

JFE is hoping to make a constructive relationship with NJTECH from now on.