On cable-stayed bridges, as on suspension bridges, steel cables bear the deck's load, but on cable-stayed bridges the cables are attached directly to the pylons. This reduces costs in comparison to suspension bridges. There is also, however, a reduction in the potential span, which, with a range of between 100m and 800m (with two pylons) is less than that of suspension bridges – even if, in exceptional cases, a span of 1,000m can be bridged. There are many types of cable-stayed bridges which are distinguishable by the pylon design (eg. A-Pylon, Y-Pylon, Middle Pylon, Two Pylon). As with suspension bridges, a defence against wind-induced oscillations is of particular importance. The solution found by the company demonstrates Waagner-Biro's know-how: it developed bridge sections with perfect aerodynamic designs.
Suspension bridges are known for their vast dimensions and they are, in fact, used to span distances of 300 to 1,500 metres. Subsequently, they are normally an impressive sight and suspension bridges often attain the status of tourist attraction.
For those attracted to the engineering: a suspension bridge has two pylons to which the main supporting cables are attached. Connecting cables, attached to the main cables, support the deck and the main beam below. It is the bridge's cables that carry the complete load. In addition to its own weight and the weight of the traffic, loads are generated by the wind, which are also transferred through the cables, along the pylons and into ground.
The plate-girder bridges – or box-girder bridges – offered by Waagner-Biro are suitable for many uses. The bridges come in many forms spanning many different distances. As composite structures, they have become economically attractive options. Their construction is of a reinforced concrete roadway set across a framework of steel girders. This combines the advantages of concrete (an economic roadway) and the advantages of steel (malleability, durability and re-enforceability). These types of steel bridges can be used to span up to about 250m.
Arch bridges are characterized by their elegant forms. Depending on the nature of the landscape over which they will stand, and the environmental conditions, Waagner-Biro construct bridges whose arches are above their decks (suspended deck), or bridges whose decks run above their arches (deck arch). Arch bridges are suitable for small constructions and for spanning lengths from 100m to 300m. It is also possible to erect many arches in a row.
If the weight of a bridge needs to be kept light, Waagner-Biro's truss bridges are a good choice. Because of the truss construction of their main support, the construction as a whole and its individual components (truss members) weigh comparatively little. This type of bridge is used for railway bridges, road bridges and other uses. Spans of up to 150m can be covered.
Not only people and their means of transport, but also oil and gas pipelines, conveyor belts, water pipelines or other heavy objects need to be transported over rivers and valleys. For these purposes, Biro-Waagner supplies pipeline bridges. These are equipped with a unique suspension system made from Y-shaped pylons that provide maximum stability. This stability is enhanced by a sophisticated central node that connects bearer cables and stay cables . This makes this type of bridge suitable for pedestrians, too. Waagner-Biro has already built many of these bridges with spans of over 300m.