How reinforced soil revolutionises construction and infrastructure stability

Reinforced soil is a technology that is revolutionising civil engineering and infrastructure construction. This innovative practice combines the use of geosynthetic materials with natural soils or granular materials to improve performance and stability.

What are reinforced soils?

Reinforced soils are engineered structures consisting of a combination of geosynthetic material, such as geotextiles or geogrids, and natural soil or granular material. These materials are used to improve the load, drainage and stability characteristics of the soil. Reinforced soil is often used in situations where unstable or poor-quality soil requires reinforcement.

They originate from construction intuitions dating back to antiquity, into which materials such as ropes, cloths or strong cloths were inserted to increase their resistance, especially to traction. This practice stems from the recognition of the fact that some materials, such as the concrete used today, exhibit high compressive strength but lower tensile strength. For this reason, in the 1960s in France, the idea was developed to insert metal elements into the earth mass in order to increase strength (mechanically stabilized earth).

Thus, the elements that characterise modern reinforced soils are the reinforcing elements represented by the geogrids and the covering of the surface by means of bio-mats and bio-textiles, applied to retain the small particles of soil that may become detached due to physical and atmospheric agents, with the task, in our case of the pre-seeded products, of greening the façade with a better environmental integration and a better aesthetic effect. The Viresco® Satorpre-seeded biotextile for example, is used for its ability to deal with critical situations while also enhancing them from an aesthetic point of view.

The use of Viresco® Sator in reinforced soil

Once the reinforced soil has been designed taking into account all the morphological, geological, hydrogeological and geotechnical variables of the situation in which it is to be worked on, we proceed to its construction by first creating the work plan. Subsequently, metal formwork of an established height and inclination is put into position. The geogrid is laid on top of these, fixing it at the bottom and at adjacent points between them.

Practicality and ease of handling also make the Viresco® Sator biotextile advantageous during the construction phase, and once the arrangement of all other materials has been completed, the pre-seeded biotextile is laid in such a way as to create a 10-15 cm flap at the bottom and at the top of the formwork. The metal stiffening rods of the formwork are then installed by piercing the biotextile according to the planned inclination.

Before backfilling, at least 20 cm of fertile plant soil is laid close to the structure that is in contact with the bio-textile fabric, compacting it slightly. The remaining backfill soil can be recovered at the site or retrieved from external sources.

The backfill soil must therefore be placed in layers and compacted in a manner appropriate to its constituent characteristics and the degree of humidity in which it is to be used, in order to avoid significant settlements at a later date after construction. In the case of reinforced soil over several levels, the operations described above are repeated until the top level of the work is reached.

Once the construction phases have been completed, and depending on temperature and sunshine, it is recommended to water the turf frequently until it is fully settled. Viresco® Sator effectively retains the finer parts of the soil and ensures its greening while achieving truly aesthetic results.

Advantages of using Viresco® Sator

The possibility of customising the essences contained in the pre-seeded biotextile allows for the best vegetative performance in the most diverse environmental and climatic conditions. Furthermore, variations are also possible according to the customer's needs, up to and including floral arrangements and colour requirements. Given the difficulty in greening these surfaces (due to slope, substrate quality, water shortage, etc.), having such a refined and perfected technical solution such as Viresco® Sator is a non-negligible and much appreciated advantage.

Reinforced soils, once they have been planted, have a well-ordered appearance, with healthy plants that fully fulfil their function from a physical, aesthetic and environmental point of view in terms of mitigating dust, noise and providing all the environmental health benefits that greenery can provide. Applied in all latitudes and geographical contexts, Viresco® now boasts 30 years of experience in geotechnics and reinforced soils, establishing itself as the best and most environmentally friendly solution for greening these types of soils.