Overview
Baker
Bridge comprises a single 42m high, steel A-frame
tower that
carries a three metre wide footway/cycleway an unusually
high 12m above carriageway level. The tower supports a
front-span of 72m and a back-span of 38m via 4 pairs
and 3 pairs of cable stays respectively. The north-side abutment of
the shorter back-span is also designed to act as a counterbalance. The
legs of the tower are protected against vehicle collision by large
concrete bases and feature simple bolted flange joints to speed
erection.
To
construct the bridge a temporary support tower was erected at the
midpoint of the longer span and the steel deck units for both spans
were assembled sitting simply supported at the supports. Once all were
in place the deck units were welded together to create a continuous
deck prior to stressing the cables to a predetermined value and an
in-situ concrete deck was cast.
Thick
beam elements modelled all members with plate elements representing
the concrete deck. Because the footbridge provides the main
pedestrian access to a rugby stadium the design of the slender deck
required a detailed time-step analysis to investigate any potential
dynamic effects that could be induced by the passage of large crowds.
The LUSAS pedestrian loading wizard was used to achieve this.
The
bridge was completed in 2007 at a total project cost of £650,000.
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