Circular soil improvement without supply and disposal of building materials

Terrastab Netherlands, specialist in soil improvements and soil stabilizations, has for many years, according to director Anton Bunt, been using the philosophy that is only now really starting to gain a foothold. "We have been focusing for twenty years on sustainability and circularity, themes that are now gaining ground. That makes that we are now experiencing strong growth." Bunt talks about the concept that allows them to do soil improvement or road renovations in an environmentally friendly way, without large-scale supply and disposal of building materials. So completely PFAS- and PFOS-free.

Over the past 20 years, Terrastab Netherlands has built up enormous expertise in the field of sustainable and circular soil improvement. "We have developed a number of sustainable and low CO2 binders to make the subsoil ready for heavy loads using the local foundation," Bunt explains. "In the countries around us it is a standardized methodology; in the Netherlands, on the other hand, we had to invest heavily in knowledge and innovation in the first few years. Our country is characterized by a wide variety of soil composition. This means that we always determine the parameters of the binder in our own laboratory on a project-specific basis on the basis of preliminary research."

Natural binders

Stabilizing foundations under roads, construction sites, dike bodies, airports, railroad lines, parking or storage areas, Terrastab Netherlands always has a suitable solution. "We can do our 'trick' with as few secondary raw materials as possible," says Bunt. "Because we compose the natural binders, such as an Ecostab or Ecosoil, completely in-house, we have built a huge lead in the market. We control the entire process from A to Z. Because we do not move any building materials and process everything in situ, an AP04 examination is not necessary. The PFAS and PFOS issues do not affect us either. Working with the existing foundation and/or building materials such as an existing road foundation provides an enormous CO2 reduction. The number of transport movements is minimal, which prevents a lot of nuisance on the surrounding area. The new stabilization layer we create can be completely reused at end of life."

Floriade

One of the recent projects in which Terrastab has made a substantial contribution is at the Floriadeterrein in Almere. "Here we stabilized a total area of no less than 53,000 m2, ranging from bus parking lots, walking paths, et cetera. The existing foundation was really a blubber puddle," Bunt knows. "Caterpillar cranes had to remove the top layer on dragline pads, that's how wet and dirty it was there. We then set to work on soil improvement to create sufficient bearing capacity in the subgrade. We then created a top course on which only 7 centimeters of asphalt was applied in the area of the bus parking lots, since the load-bearing capacity is taken from the foundation construction. For the walkways, only a wearing course was applied to the top road. When the Floriade ends in October this year, the asphalt will be removed for reuse elsewhere, we will mill down the stabilization layer and return it as soil to nature."

Our natural binders are 100 percent recyclable, circular and comply with the Soil Quality Decree (Bbk), Bunt summarizes. Terrastab's technology is also proving its added value in road renovations. "We just completed a beautiful project in Leimuiden. The asphalt was worn out and the old foundation showed cracks. In a very short time frame, together with Versluis Groep from Bodegraven, we renovated the entire road construction over a length of some 3,600 meters with a closed soil balance. A textbook example of a circular road renovation with minimal inconvenience to the surrounding area."