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Special Feature 
Newsletter "SEI WORLD" Vol.455

Prestressed Concrete (PC )-related products

[Photo] Matoba Viaduct (Shizuoka Prefecture, Shin-Tomei Expressway)
[Photo courtesy]: Sumitomo Mitsui Construction Co., Ltd.

This article features prestressed concrete (PC)-related products offered by Sumitomo (SEI) Steel Wire Corp., one of our group companies.

PC business of the Sumitomo Electric Group

In 1958, Sumitomo Electric introduced long-span concrete bridge construction technologies from Dyckerhoff & Widmann AG (Dywidag) in then West Germany, and has expanded manufacture and sales of PC steel components in Japan.

The Sumitomo Electric Group operates a mother plant of Sumitomo (SEI) Steel Wire Corp. (on the premises of the Itami Works), manufacturing bases in the US (California and Tennessee) and Indonesia, and a joint venture in China which specializes in corrosion-resistant coating.

[PC steel components] Features and application areas of PC steel components

PC strands
PC strands

PC strands, which are the Company’s main products, are made from high carbon steel (carbon content: about 0.8%). They serve as the key components of PC structures characterized by high tensile strength and superb toughness. PC steel components are used in various areas of social infrastructure including highway bridges, railway bridges, slope stabilization anchors, wind power generation facilities, building structures with large interior spaces, and tanks.

PC steel components are highly resistant to tensile force.

A PC strand of about 1.5 cm in outside diameter can withstand the weight of about 20 passenger cars (about 20 t).

[Highly functional PC steel components] Highly functional PC steel components that meet the needs of the market and society

The Sumitomo Electric Group develops and offers various highly functional PC steel components, including corrosion-resistant coated PC steel components whose design service life is 100 years and high-strength PC steel components of 2,230 MPa class (among the highest in the world). These PC steel components are designed to meet the needs of the market and society, contributing to development of today’s PC structures

PC structures that underpin the social infrastructure

Tsubasa Bridge (Southern Economic Corridor in Cambodia) *1 Cable-stayed bridge
Tsubasa Bridge (Southern Economic Corridor in Cambodia) *1 Cable-stayed bridge
D runway at Tokyo International Airport (Tokyo) *2 Super Quality Cementitious Material (SUQCEM) floor slab
D runway at Tokyo International Airport (Tokyo) *2 Super Quality Cementitious Material (SUQCEM) floor slab
Steel fiber for high-strength reinforcement
Steel fiber for high-strength reinforcement
Sanagawa Bridge (tentative name) (Aichi Prefecture, Shin-Tomei Expressway) *3
Sanagawa Bridge (tentative name) (Aichi Prefecture, Shin-Tomei Expressway) *3
Matoba Viaduct (Shizuoka Prefecture, Shin-Tomei Expressway) *4
Matoba Viaduct (Shizuoka Prefecture, Shin-Tomei Expressway) *4
Offshore wind power generation system (off the coast of Choshi, Chiba Prefecture) *5
Offshore wind power generation system (off the coast of Choshi, Chiba Prefecture) *5

[Photo courtesy]

*1  Sumitomo Mitsui Construction Co., Ltd.

*2,*3,*5  Kajima Corporation

*4  Central Nippon Expressway Company Limited

*5  Used for collaborative research by NEDO (New Energy and Industrial Technology Development Organization) and Tokyo Electric Power Company, Incorporated

Highly functional PC steel components and related products that underpin the quality of structures

Highly functional PC steel components and related products that underpin the quality of structures

[Photo courtesy]

*6  The Zenitaka Corporation

Highly functional PC steel components and related products that underpin the quality of structures

Prestressed concrete refers to concrete which is subjected to stress in advance to dramatically increase its load-carrying capacity and durability. The structure represents the ideal combination of concrete, which is resistant to compressive force but weak to tensile force, with PC steel components, which are resistant to tensile force. Cracks caused by tensile force (Fig. A) contribute to deterioration of the structure. In the case of PC (Fig. B), generation of cracks is minimized due to the compressive force that is applied in advance, helping maintain structural integrity.


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