Tackle deep cracks in the asphalt with piles made of reusable debris. That is the idea behind a trial that the municipality of Emmen has started together with local road builders. It remains to be seen whether this method is an answer to damage to the road surface caused by subsidence.
Three bone-dry and hot summers in a row have caused the subsoil of a number of roads and cycle paths in the municipality of Emmen to subside. This results in deep cracks in the asphalt. Due to the dry weather, the groundwater level has become increasingly lower, causing the underlying peat to settle.
A start has now been made with the test on the Scholtenskanaal Oostzijde in Klazienaveen-Noord. It is a road known for its extremely bumpy character. “Here we are testing a sustainable technique that produces fewer emissions and protects the trees along the road,” explains alderman René van der Weide.
The road builders involved use a new technique in which the subsidence is tackled with gravel cores. These are piles made of reusable debris. This is poured into drilled holes in the road surface. The underlying peat layer is filled up again with the gravel piles. This creates a solid layer in the deeper subsoil.
“The advantage of the reinforcement with piles is that the top of it is a solid basis for the new road surface,” says the alderman. Another advantage, he says, is that trees are spared because there is no need to dig. “That saves 150 lorries with sand that don’t have to drive back and forth. This is the case with a normal approach.”
If the test with gravel piles is successful, the municipality also wants to use this technique on other damaged roads.