The Santhià viaduct on the Turin-Novara
section of the high-speed, high-capacity Turin-Venice railway
line, which has been in function since February 2006,
is composed of 25 and 20.50 m spans, simply supported
on the piers, for a total length of 3,783 m; the deck is made
of single-cast box girder. The measurements of the track
level carried out evidenced a particular trend in longitudinal
level along the viaduct, with depressions over the piers
and peaks at the centres of the spans. This phenomenon
was attributed to the fact that the curing times of the concrete
before regulation of the track were so reduced that
part of the viscous deformation of the deck, that relative
to pre-compression and self weight, occurred after the
track was laid. This phenomenon is illustrated herein, and
an analytical evaluation of the abovementioned hypothesis
was carried out by definition of creep curves from the
most evolved international technical regulations. Finally,
an evaluation of any future repercussions on the use of
the structure was carried out.
- Febbraio