useful remaining life to 40 years. Until the electrification of the Waldshut–Koblenz gap in 1999, passenger services on the bridge were carried out by diesel multiple units of Deutsche Bahn. From 1999, SBB took over management of services on the bridge using electric multiple units. In 2007, about 34 trains daily operated as line S41 of the Zürich S-Bahn between Waldshut and Winterthur. In late 2011, the SBB introduced refurbished Class 560 electric multiple units to the S27 line. Unfortunately the refurbishment, which included the introduction of air conditioning, took the axle loading of a fully loaded power car over the maximum for the bridge. As a temporary solution, the power cars were locked out of use whilst passing over the bridge, and the trains limited to . Following work on the bridge, these restrictions were lifted in early 2014. Construction The c. bridge section has a track on the upper level of the truss bridge and its spans over the Rhine consist of two outer spans that are long and a central span of . This is followed on the Swiss bank by a brick viaduct with six semi-circular arches, having an inside diameter of . The greatly varying spans of the main bridge result from the nature of the currents in the Rhine. On the German side, after the line runs on an embankment for some , it crosses over the E54 on a modern concrete arch bridge. The superstructure of the lattice truss bridge is made of wrought iron and is box shaped in cross-section. At has a continuous beam along its length. It has two vertical close-knit, grid-like lattice truss with a height of and a track base of . The diagonal struts are formed from flat steel and riveted together at the intersections. The vertical pillars consist of four riveted corners. The foundation of the pillars are built on driven wooden piles that are about long, topped by concrete pile caps. The tops of the pillars are high and wide and made of stone masonry. Assembly The superstructure of the current bridge was assembled in three sections on the Waldshut bank in a temporary work hall. After completion of the first segment, it was rolled out of the hall. Then the second segment was built, and on its completion was connected with the first. Finally, the third segment was built and the entire length of