Aluminum foam noise barriers: one panel that absorbs, does not burn and does not rust

Noise barriers are the most demanding place a panel can be. They stand beside traffic in the weather for decades, they are hit by spray, salt, sun and the occasional vehicle, and nobody wants to maintain them. The material that fills that brief has to absorb sound, cannot burn, cannot rust, and has to be light enough to stand on a simple post and rail. Aluminum foam is one of the few single materials that does all of this, and it has been in service on roads and rail lines for years.

Absorbs

A conventional metal barrier reflects traffic noise, which solves the problem on one side by sending it to the other. An absorptive barrier takes energy out of the sound instead. Aluminum foam's open cellular surface, backed by a cavity or a dense layer, is an absorptive surface in a single non-combustible panel, without a perforated skin over mineral wool that has to be kept dry. Absorption figures depend on the barrier grade and build-up and are published with project data.

Does not burn

Barriers beside roads, in tunnels and on rail corridors are increasingly required to be non-combustible, and plastic or composite absorptive panels are being replaced for that reason. Aluminum is non-combustible. A foam panel adds no facing, core or adhesive to the fire load.

Does not rust

Aluminum protects itself with its own oxide layer. A barrier panel made of it needs no galvanising, no paint and no maintenance cycle. That is the quiet economic argument: a slightly higher panel cost against decades of nothing.

Where it fits

• Highway and arterial road barriers, especially where an existing reflective barrier is being upgraded to absorptive.
• Rail corridors, where non-combustibility and no maintenance access are both required.
• Tunnel portals and trench walls, where absorption at the opening matters most.
• Plant screens and substation enclosures, where the same panel does noise and weather in one.

Working with VORALOY on a barrier

Barrier projects are quoted per project, with panel size, grade and build-up agreed against the specification. If you are writing a barrier specification or evaluating a replacement for an existing system, get in touch with the corridor, the required performance and the timescale. For other uses of the material, see Applications.

Hold the material before you decide. The Standard Sample Kit is one 300 × 300 × 20 mm panel; the Designer Kit is three cell grades side by side. Both ship free within the United States.