Airex, Baltek, Banova, AirexBaltekBanova
Building | Construction

First sandwich bridge in Switzerland

Innovative construction is a tradition in Switzerland. The replacement of a road bridge that was approximately 100 years old and crossed the river Avançon near Bex in the Swiss canton Waadt with a lightweight bridge by 3A Composites follows this tradition very well.

The objective was to minimize traffic interruption and to expand the bridge to two lanes - with the existing substructure. The complete pre-assembly could be performed next to the construction site itself due to the low weight of the deck, which was then lifted into place with a crane.

3A Composites, together with EPFL and leading industry partners, developed the COLEVO bridge deck in fiber composite/sandwich/lightweight construction technology. Two high-strength, stiff FBE face sheets absorb the side loads of the COLEVO sandwich deck sheet and the newly developed structural BALTEK® core, which is based on balsa veneer, transmits the shearing forces. The high loads of a road bridge are easily absorbed by the vertical alignment of the wood fibers - despite the BALTEK® core's low density of only 260 kg/m³.

If low weight and high durability are required for construction applications, the COLEVO lightweight construction method proves to be a highly competitive solution when taking a look at total costs.

For construction on difficult substrates, in close quarters, or in locations that are difficult to access, a lightweight construction method may be the only possible solution.

The bridge owner (Canton Waadt) says this in regards to the COLEVO construction method during the construction: "The most important advantage for us was the light weight of the deck. This allows us to work with smaller machines. We will also see this in one week, when the bridge is put into place in one go - in one piece. Another advantage is that it can be installed in only two days.“


  • 7.5 m x 11.4 m
  • 3 components on steel beams, structurally cemented, pre-installed next to the construction site.
  • 600 kN + 400 kN axle loads
  • COLEVO deck 13.5 t
  • Can be installed with a crane due to the low weight to be raised.
  • Installation in October 2012, with only a few days of traffic interruption and installation in only 2 hours
  • Broader bridge plate
  • Existing foundation was not changed
  • Maximum durability and low maintenance

Expertise without borders

lightweight core material for aircraft construction

> more

Building | Construction

FreeRIDE skiing made easy

foam and balsa sandwich solutions for industrial applications

> more

Tailwind with AIREX®

Airex, Baltek, Banova, core materials for marine applications

> more

Make way for AIREX®

Airex, foam composite materials for rail applications

> more

The market leader's wings

Airex, Baltek, foam and balsa composites for renewable energy

> more

Lightweight for heavy loads

Airex, Baltek, foam and balsa composite materials for road applications

> more