Repair and reconstruction of engineering structures - Assessment and Refurbishment of Steel Structures - page 187

Chapter 6
Repair and reconstruction of engineering
structures
6.1 Bridges and special structures
6.1.1 Cable bridge systems
6.1.1.1 Introduction
The number of cable systems has increased considerably over the last three decades
thanks to their well-known advantages. Beside their economy, this has also resulted from
the development of new architectural forms in the design of bridges and land
constructions with large spans.
Along with their advantages, cable systems also have their disadvantages. Notable
among these are their greater deformability, the danger of vibration, and thereby also the
possibility of cable breakage, especially at and around the anchorage. Protecting cables
against corrosion is more complicated than in the case of contemporary steel structures.
In many types of cable system, when just a single cable breaks, this can lead to an
unfortunate rearrangement of the internal forces that can cause collapse of the whole
system.
6.1.1.2 Correcting the off-centering of the bridge of the Cabin Cable
Railway
In 1988-9 the technical condition of the cable bridge of Cabin Cable Railway at Start in
the High Tatras was assessed (Figure 6.1). At this bridge, incorrect feeding of the cables
into the pulleys was a regular occurrence [64]. The expert assessment revealed that a steel
structure had been wrongly erected, resulting in a linear slewing of the main girders of
the bridge ranging from 8.0 to 169 mm in the plane of the plan (Figure 6.2).