Winter 2016

Solution for a new stone age

Currently, rainwater often disappears down the drain instead of being collected underground. This has consequences for soil conditions, installation capacity for sewage treatment, and the bacterial decomposition of dirty water. Aquabase contributes to solving this problem. Based on two geosynthetic materials, it can be applied in road construction. 

The Netherlands paves and concretes. The increasing intensity of rainfall means considerable water falls in a short space of time, and much of that rainwater from roofs, streets, pavements and paved gardens is quickly transported via the drainage network and storm drains in the street to the sewage treatment system. Often traditional drainage is unable to deal with this. The result? The Netherlands is becoming dry and the capacity of the sewage treatment system must be enlarged.

4 geosynthetics Aquabase Potgieterstraat, Nijverdal (21)
Beginning of construction with Aquabase, 
TenCate Accorder® and TenCate Polyfelt®

Because dirt mixes with rainwater, the bacteria in the sewage treatment system that normally ‘eat’ the waste materials and help to clean the water function less efficiently. This is at odds with the obligation of municipalities to halve the rainwater discharged to the water authorities no later than 2020. Aquabase goes a good way to solving the problem. It is a stable, water-buffering road foundation that helps the rainwater to infiltrate the subsoil. There are two types: one that can be installed without storm drains, and a version with storm drains for a clayey, more poorly permeable subgrade. 
4 geosynthetics Aquabase Potgieterstraat, Nijverdal (43)
TenCate Accorder® ensures a stable and stabilising base course, whereby less soil has to be excavated 

The Aquabase system is a joint development of Van den Bosch Beton (concrete paving products), Rotim (raw materials for infrastructure) and TenCate Geosynthetics. The basis for the system is TenCate Accorder®. This subbase has been developed primarily to provide a stable base course for synthetic turf fields. It helps to reduce the costs – for example of earthwork – involved in installing a synthetic turf field.

4 geosynthetics Aquabase Potgieterstraat, Nijverdal (7)
TenCate Accorder® is composed of pockets (compartments) approximately 7 by 7 centimetres, which can be filled with local sand, gravel or rubble

For a stable base layer, TenCate Accorder® is filled with very coarse hard limestone gravel in in the gradation 8/32 with 34% hollow space. The engineering firm TAUW calculates the buffer capacity, which determines the thickness of the base layer. TenCate Polyfelt® TS10, a robust and durable non-woven geotextile with high permeability, is then applied to the sides and top. And so a stable base layer is created. On top comes the footing or street layer: a 3 to 5cm-thick layer of 2/8 hard limestone gravel from Rotim. This is paved with Ecopass® permeable stones from Van den Bosch Beton. These allow water to pass through at a speed of 4,000 litres per second per hectare. The stones have relatively wide joints.

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Nowadays, rainwater in new residential districts is already kept separately above ground. In residential districts where this is not feasible because available public space is inadequate, Aquabase also offers a sustainable solution.  

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Where possible, the various components of Aquabase are undergoing further development. For example, bacterial additives can be added to the non-woven to break down oil residues attributable to car traffic. 
Watch the animation.

Blue fabric (Tecawork Blue 65287)