A stress ribbon
bridge is a tension structure, similar in many ways to a simple suspension
bridge. The stress ribbon design is rare. Few people including bridge engineers
are familiar with this form and fewer than 50 have been built worldwide. The
suspension cables are embedded in the deck which follows a catenary arc between
supports. Unlike the simple span the ribbon is stressed in compression which
adds to the stiffness of the structure. Such bridges are typically made from
concrete reinforced by steel tensioning cables. They are used mainly for
pedestrian and cycling traffic. Stress ribbon bridges are very economical,
aesthetic and almost maintenance free structure. They require minimal quantity
of materials. At present studies, on combining stress ribbon bridges with
cables or arches, to build most economical stress ribbon bridges. It makes the
study of features of these particular bridges as an important one.
A stressed ribbon
bridge (also stress-ribbon Bridge) is a tension structure (similar in many ways
to a simple suspension bridge). The suspension cables are embedded in the deck
which follows a catenary arc between supports. Unlike the simple span the ribbon
is stressed in compression, which adds to the stiffness of the structure
(simple suspension spans tend to sway and bounce). The supports in turn support
upward thrusting arcs that allow the grade to be changed between spans (where
multiple spans are used). Such bridges are typically made from concrete
reinforced by steel tensioning cables. Where such bridges carry vehicle traffic
a certain degree of stiffness is required to prevent excessive flexure of the
structure, obtained by stressing the concrete in compression.
Stress Ribbon Bridges
Philosophers, thinkers, intellectuals all appeal, please build bridges and not
walls between different communities, nationalities, countries, languages etc,
to achieve universal brotherhood. This can be achieved by constructing stress
ribbon bridges. Stress ribbon bridges are very economical,
aesthetic and almost maintenance free structure. They require minimal quantity
of materials. They are erected independently from the existing terrain and
therefore they have minimum impact upon the environment during construction.
Stress ribbon bridge is the term used to
describe structures formed by a very slender concrete deck in the shape of a
catenary. They can be designed with one or more spans and are characterized by
successive and complementary smooth curves. These curves blend in to natural
environment and their forms, the most simple and basic of structural solutions.
The stress ribbon bridge can be erected without undue pressure on the
environment.
Stress ribbon bridges looks at how slender
concrete deck are used in the design of suspension and cable stayed structures.
It looks at their characteristic feature; their rigidity, which is mainly given
by the tension stiffness of prestressed concrete decking so much so that
movement caused by pedestrians or wind does not register as discomfort by
users. As opposed to suspension bridges, where the cables carry the load, in
stress ribbon, by tensioning the cables and the deck between the abutments, the
deck shares the axial tension forces. Anchorage forces are unusually large
since the structure is tightly tensioned.
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