Three kilometre of motorway near the
Dutch / German border: An alternative bid by a consortium won the contract and reduced the costs of construction significantly.

An economic alternative for roads: granova® IBAA

The 3 km section of the autobahn A 61 between Venlo (Netherlands) and junction Kaldenkirchen (Germany) was constructed using IBAA. The highway was specified as an asphalt construction and included five underpasses as well as an entrance/exit. A particular challenge of this project was the extremely high quantity of material needed for the earthworks along the planned route.

granova road works a61

The 3 km long autobahn route near the Dutch/German border

Ideal conditions for secondary aggregates

The Lower Rhine regional office of the North Rhine-Westphalian State Office for Road Construction (StraßenNRW) called for primary building materials in the call for tenders – the use of secondary materials was initially not considered.

However, the construction project was also suitable for the use of secondary materials. The site is situated outside of water protection areas and construction under an asphalt layer is water impermeable – allowing the use of Incinerator Bottom Ash Aggregate (IBAA). A minimum distance of one meter between the secondary material and the highest groundwater level was given, as was a minimum distance of half a meter from corrosion-prone buildings. As a result, all the conditions for the use of substitute materials were fulfilled.

A bidding consortium of companies decided to also submit an alternative bid during the tender process, which specified the use of IBAA for the fill instead of required primary building materials. This resulted in a significant cost reduction of the project. The NRW road construction authority as investor was convinced of the method and awarded the contract to the consortium.

High speed construction

Over a period of only 6 months, a total of 250,000 tonnes of IBAA were incorporated into the subgrade.

granova road works A61 krefeld

A61 during construction

145,000 tonnes of IBAA of granova® quality were supplied by the MAV Mineralstoff-Aufbereitung und -Verwertung GmbH (a REMEX affiliated company) from their premises in Krefeld and Erftstadt.

At peak times, up to 6,000 tonnes per day were delivered. The complete autobahn section was finished after a record-breaking construction time of one year.

Facts at a glance

  • Project owner: North Rhine-Westphalian State Office for Road Construction (StraßenNRW)
  • Two lanes over 3 km under asphalt pavement
  • Required traffic exposure class SV (heavy traffic, motorway)
  • Use of 250,000 tonnes of IBAA as fill in the subgrade
  • Delivery of 145,000 tonnes of IBAA in granova® quality
  • Delivery of 6,000 tonnes per day at peak times
  • Contractor: “Neubau A 61” consortium, consisting of Frauenrath GmbH and Willy Dohmen GmbH & Co. KG
  • Supplier of IBAA: delivery by MAV Mineralstoff-Aufbereitung und -Verwertung GmbH, a REMEX affiliated company and granova® partner