Overview of stress ribbon bridges made from timber
Timber as the tieback
The basic concept is a traction system which is back-tensioned to the end abutments. This streamlined tieback consists either of a block-bonded laminated timber panel or individual laminated timber supports which are braced downwards with intermediate supports. A certain sag is a static requirement in order to reduce the tensile force.
On its top side, the supporting structure has a roadway surface with a thick mastic asphalt or a sheet metal covering with an overlaid surface so that an optimum structural protection of the timber is achieved.
The railings are attached to the side of the main girders.
With stress ribbon bridges, optimum use can be made of the positive attributes of timber such as its high tensile strength and high dimensional tolerance in parallel to the fibre.
In this way it is possible to create very streamlined and aesthetic constructions which are also efficient with long span widths. The necessary sag is to be ensured, especially in terms of accessibility, but can also be reduced by duplications.