Mountainous (alpine) areas account for more than half of Austria, so motorways and other civil engineering structures in these regions are faced with a substantial number of natural hazards, such as avalanches, ground displacements, mudflows and falling rocks. These can damage, block and undermine roads. Still, retaining walls reinforced with TenCate geosynthetics prove a godsend as a rule when it comes to repairing and preventing the consequences − as two recent projects go to show.
The mountain road near Rodlau rested on a soil structure that was deteriorating through the action of discharged water. Soil reinforcement and modification of the bend in the road at that point were recommended. Option 1 was to build a bridge more than 100 metres long: cost: € 1 million. Option 2 was to construct a 30-metre (64°) slope reinforced with TenCate Polyfelt® Rock GX against the mountain wall: cost: € 410,000. The decision was quickly made. After the reinforced structure had been built in 2005, work could start in 2006 on laying the road and introducing vegetation. Any deformations in the construction that occurred during and after the installation were registered with TenCate Geodetect®.