Building on its legacy of excellence, Waagner Biro Bidge Systems has pushed the limits of what was thought possible in steel bridge engineering space.

Today we offer the following solutions:

SPECIAL
Bridges

CABLED-STAYED BRIDGES

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.

Span: 100-800m (1,000m)

SUSPENSION BRIDGES

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.

Span: 200m – 2,000m

PLATE-GIRDER BRIDGES

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.

Span: 30-250m

ARCH BRIDGES

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.

Span: 80 - 300m

TRUSS BRIDGES

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.

Span: 30-150m

PIPELINE BRIDGES

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.

Span: 100 - 500m

Moveable Bridges

BASCULE BRIDGES

Bascule bridges are impressive examples of the art of modern engineering. To enable ships to pass, one or two of the bridge's sections are raised and then lowered again. Bascule bridges are often chosen for places like urban areas that don't have enough space in which to build the high approaches required for conventional types of bridge. The emphasis is on causing as little interruption as possible to the flow of traffic both crossing and passing under the bridge. Therefore, the greatest challenge is to have the shortest possible opening and closing times. Waagner-Biro's Bascule bridges require opening times of between 90 and 180 seconds, depending on the requirements of our customers. Bascule bridges must operate with a high degree of reliability.

If a defect prevents a bridge from opening or closing, there are serious consequences on the flow of traffic. This means that the bridge's core element is its drive mechanism. Today, electro hydraulic drive mechanisms with hydraulic cylinders are the most economic type of drive mechanisms. They guarantee maximum effectiveness with the minimum of maintenance.

SWING BRIDGES

Swing bridges often move loads of over 1,000 tonnes in just a few minutes, thereby freeing a shipping channel. They are particularly suited as river crossings when high street or rail bridges are considered too expensive or would have too great an impact on the environment. When bridging major shipping channels, it might be advantageous to combine swing bridges and fixed bridges. When this option is chosen, the complete bridge structure has a higher crossing so that the headroom is sufficient for normal shipping and the swing bridge only has to be opened for the largest ships.

Most swing bridges are built as symmetrical structures with a central pillar so that two shipping lanes with unlimited headroom are available, one on either side of the pillar. Like all movable bridge systems, swing bridges must function quickly and efficiently to ensure an uninterrupted flow of traffic.

VERTICAL LIFT BRIDGES

The traditional vertical-lift bridge has, up to now, been used to bridge rivers in crowded urban environments. They do, however, have a limited headroom for shipping traffic. The bridge's supporting structure is made of steel. This reduces the weight which needs to be raised and makes an operating hoist economically viable. A vertical-lift bridge is supported by cables which are usually connected to counter-weights that are positioned at the bridge's four corners. This compensates the bridge deck's weight and any residual load is raised and lowered using a winch.

A perfect example for a lift bridge is Botlek Bridge, the worlds largest lift bridge, situated in the harbour of Rotterdam, Netherlands. Waagner-Biro was awarded the European Steel Bridge Award 2016 for the construction and erection

Flyover
Ramps

FLY-OVER RAMPS

A flyover ramp is a bridge construction that is placed on a bridge to allow repair and maintenance work to be carried out on the bridge structures without disrupting traffic flow. The components consist of a modular construction system with plug-in and threaded connectors to ensure quick and safe erection. The modular system can extend over up to four lanes and reach a length of up to 106 m. A special arrangement of bearers and braces transfers the traffic and wind loads to the bridge underneath; no additional anchoring is required. The special road surface provides optimum tyre grip.

One of the advantages of this robust and reliable structure is that it is reusable. A safe working space of 1.9 m in height allows work to be carried out without interruption. Despite the fact that the flyover ramp is not very heavy in itself, it can be used by heavy lorries and is also able to accommodate any movement of the bridge underneath.

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