Draw pits and slanting tops of a new material

This is how they solved the problems on the new E18

Draw pits and slanting tops of a new material:

This is how they solved the problems on the new E18

The slanting tops were specially made for the assignment and weigh in at 18 kilos per piece.

Foamrox has launched a number of recycled glass construction products which can replace concrete. On the new European road between Tvedestrand and Arendal, new slanting tops were used to solve problems in sloping terrain.

“The draw pits had the wrong angle and profile in relation to the trenches, so I contacted Foamrox in the hope of finding something smart,” says Jørgen Olav Nes, Operations Manager of AF Anlegg.

In collaboration with Foamrox, they came up with slanting tops that could be mounted directly onto the draw pits, which solved the problems in sloping terrains.

“We've now installed 25 slanting tops on the E18 between Arendal and Tvedestrand and this is a product that works very well,” the Operations Manager reports.

Made of recycled glass

Foamrox draw pit mounted by Hæhre Entreprenør in the Vadheim tunnel on county road 55.

The Foamrox products contain a core of cell glass, which is expanded recycled glass, and have an outer coating of polyurea, known as one of the world's strongest materials.

It gives the products a number of advantages when compared to competing products made of concrete.

“We've previously installed draw pits of the same material. The big advantage is that they don't weigh very much and are therefore very easy to assemble,” says Nes from AF Anlegg.

10 draw pits on the E6

Construction Manager Kristian Sabel at Veidekke was also left with the same experience after mounting ten draw pits on the E6 between Arnkvern and Moelv.

Easy creation of holes with an electric drill.

“We wanted to test this product and ordered 10 draw pits. The feedback has been very good. You don’t have to use large machines to transport them. They are so light that two men can lift the pit into place and drill the holes with a hole drill. The product has major benefits in terms of health, safety and environment (HSE),” says Sabel.

“We could just lift the pits into place and use a hole saw for the holes in the pit. The mounting was far easier than with traditional concrete pits. If I would point out something that could be better, it would be that it should get joints with different dimensions, seeing as there are usually changes,” says Knut Hermanrud of Hæhre Entreprenør, who installed 14 draw pits in the Vadheim tunnel on county road 55 during the summer and autumn of 2019.

The strength test by Norconsult and AF Gruppen

In December, the Foamrox draw pits underwent a full-scale strength test performed by Norconsult. The three tested products all proved to be capable of satisfying a load of up to 20.3 tonnes.

"The test must be said to have been very successful and valid, seeing as all the results from the different elements that were tested coincide," the report concludes.

The Arendal-based company, Foamrox AS, already supplies a number of products for tunnels. These include fire barriers, emergency cabinets, emergency passages, fire water connection caps, fire walls and draw pits. In the future, the goal is to dress the entire tunnel ceiling with elements from Foamrox.


The total weight of all 25 slanting tops is only 450 kilos.

“These super lightweight products can help meet the ever-increasing demands of the construction industry for increased sustainability, better personal safety and faster construction times. Extensive use of recycled raw materials, combined with very low greenhouse gas emissions in terms of production, transport and assembly, make Foamrox products a very good alternative to current solutions. The low net weight (less than 10 percent of concrete) reduces the need for mechanical lifting equipment during the assembly phase, as well as the fact that it is very easy to drill holes for draw pipes in the draw pits,” says Kjell Håkon Helgesen, General Manager of Foamrox.

Foamrox draw pit lid EI60, 30 kg weight. The lid is not intended for traffic loads, but can, for example, be used on alignment edges in tunnels.


These are the Foamrox products:

·       The core of the product itself consists of cell glass, which is recycled glass. On the outside the product is covered with polyurea, known as one of the world's strongest coatings materials.


Foamrox draw pits:

·       Foamrox draw pits are an alternative to current draw pits made of concrete

·       The weight of the Foamrox draw pit comes in at less than 10 percent of concrete, it contains no iron reinforcing and there’s no need for core drilling.

·       The expected lifespan is over 100 years

·       They're waterproof and insulate in a similar way to standard building insulation.


Helgesen says the company can supply draw pits of all kinds of sizes.

“We have standard draw pits in stock for immediate delivery throughout the country. At the same time, we can quickly produce customised solutions, including super-light lids that can be handled by hand where needed,” he says.

Embraced by the construction industry

Several construction industry leaders believe that Foamrox's products will be seen in tunnels or along Norwegian roads in the future.

“I think the product quite clearly has a future. What is also exciting is what one can otherwise use this product for. I know they are already thinking of elements for technical installations or for the tunnel wall itself. I can definitely recommend the draw pits,” says Kristian Sabel from Veidekke.

“The slanting tops are a product we need for the future. Without a doubt,” says Jørgen Olav Nes from AF Anlegg.