Maintenance of steel bridges on Honshu-Shikoku crossing

Abstract

This paper describes maintenance technologies of Honshu-Shikoku bridges in Japan. The Honshu-Shikoku bridges feature many long-span cable supported bridges. Akashi Kaikyo bridge is known as the longest-spanned suspension bridge, and Tatara bridge is known as the longest-spanned cable stayed bridge. The Kojima-Sakaide route, the so-called Seto Ohashi bridge, features highway and railway combined structures. Since the opening of the first bridge, maintenance technologies of Honshu-Shikoku bridges have been accumulated for about 20 years. The most important maintenance technology for steel bridges on the sea is how to protect steel members from corrosion. In this paper, as examples of anti-corrosion methods for steel bridges, repainting of bridges by heavy-coated paint, the dehumidification method for the cables of suspension bridges, and the anti-corrosion method for the steel caissons in the sea are described. Furthermore, a monitoring system to detect weld defects in the railway structures related to fatigue problems is described. Lastly, measurement of the static and dynamic behavior of bridges to verify design assumptions on a bridge’s behavior and to ascertain a bridge’s soundness is described.