Author(s)

S. Mohri & Y. Sato

Abstract

Aluminum-based rigid conductor lines have been widely used for tunnel sections due to a cost-saving factor and their lightweight structure. Aluminum, however, is easily corroded, and it is therefore important to understand the corrosive characteristics of aluminum under the practical environment. The corrosion of the conductor lines inside the tunnel section is mainly due to groundwater seepage, containing alkali components or seawater. The authors carried out an accelerated corrosion test with an aqueous solution of sodium hydroxide to comprehend the corrosive characteristics with alkali components. Another problem is a corrosion that is likely to occur at areas where different materials contact each other. The authors also carried out saltwater spraying tests for the contact area of aluminum-base and bronze contact wire with various corrosion resistances to investigate the corrosion caused thereby. The results of these tests are described elsewhere in this paper, and the authors have indicated the predicted lifetime of aluminium-based conductor lines under the various environments. Keywords: corrosion, rigid conductor line, aluminum, tunnel section, water seepage. 1 Introduction Rigid conductor lines have been widely provided with tunnel sections or subway systems because the height of power collection equipment can be lowered. Aluminium-based rigid conductor is especially effective for power collection quality due to its lightweight structure. Aluminium however easily corroded [1], it is therefore important to understand the corrosive characteristics

Keywords

corrosion, rigid conductor line, aluminum, tunnel section, water seepage.