On concrete pavements, cracks and damaged joint seals can allow surface water to penetrate the pavement slab and wash away the subsoil. The hydraulic undermining of the pavement slab can weaken the structure and lead to damage of the paving surface. When the subsoil also is low in permeability and unable to discharge the water that has penetrated the slab, water can build-up at the interface between the slab and the prepared subsoil. Cyclic traffic loading can then subject this water to alternating high and low pressures. This «pumping» action can drive soil out from under the slab, reducing the structural integrity of the pavement.
When installed between the pavement slab and its subsoil, Secutex® PP mechanically bonded nonwoven geotextiles provide a horizontal drainage path for water to discharge before it can cause damage to the road structure. As the drainage capacities of Secutex® geotextiles are considerably higher than that of engineered soils and as they are not affected by wash-out or pooling, they protect the integrity of the pavement against hydraulic damage. The thick threedimensional geotextile also acts as a cushion against traffic vibration, helping to prevent cracking, while the open porous structure of Secutex® aids the setting and curing of in-situ cast paving slabs.
Typically, a 500 g/m² product (Secutex® type R 504) is used for this application.