Causes and analysis of steel structural failures - Assessment and Refurbishment of Steel Structures - page 50

Figure 2.30 (a) Stored paper, (b) the
steel structure after fire
2.5.4 Effects of accidental events
Accidental events that lead to failures of structures include:
• Overloading caused by extraordinary circumstances (change of marginal conditions due
to unexpected reduction of support, landslide, climatic disasters, vehicle collisions)
• Loss of strength, change in physical properties of materials (fire, large temperature
changes, chemical affects)
• Seismic influences and the natural calamities
• Failures of technical equipment, explosions and other accidental events.
The failure of the masts carrying 2×400 kV electric wiring in Slovakia is a special case of
the effect of an accidental event. Figure 2.31 shows the positions of masts from No.69 to
73 involved in the failure, and also the span of the conductors. Mast No.72 of RV type
(II) was the fault point in the wiring track, and
Figure 2.31 Position of the collapsed
masts