We fill underground cavities

    What is your need? 

    Filling underground cavities, barrels, or cisterns under or near a house or other buildings? Securing a structure that rests on a man-made or natural underground cavity?
    Instability of underground silos or cisterns due to the presence of a man-made or natural underground cavity?
    Filling unused conduits or pipes that threaten the stability of the overlying structures?
    Lightening a railway or road embankment?

    Filling underground cavities with expanded clay and injections of expanding resin.

    Our solution allows you to fill an underground cavity (man-made or natural) by pumping in Leca® expanded clay with a controlled grain size and then injecting Uretek Geoplus® expanding resin with a high and immediate expanding force. Using expanded clay, we prevent the surface from collapsing due to the unexpected failure of the cavity walls, and with the precompression produced by the expanding resin, we avoid subsidence on the surface due to the simple deformation of the walls themselves. Combining expanded clay and expanding resin, we completely solve the problem. We fill the inner volume of the cavity, compacting the grains in the fill and ensuring the pre-established precompression force in the walls.

    The advantages of the Uretek solution for filling underground cavities:

    We work on commercial, industrial, and civil buildings and infrastructure to restore operational safety without interrupting your work. We make a clean, immediately effective intervention.









    • We restore continuity between the filled cavity and the terrain.
    • Uniform distribution of stress on the ground
    • No changes in water flows
    • Use of fill materials with different resistance and deformability depending on the soil surrounding the cavity
    • Limited strain on the subgrade of the cavity and therefore limited pressure on the walls
    • Allows for temporary interventions since the fill material can be removed
    • Can be applied without accessing the cavity
    • Stable ‘contact’ over time between grains of clay and between the grains and surface of the cavity
    • Can also be applied to cavities separated by tens of metres from the nearest reachable point
    • Safe and precise monitoring due to the laser system
    • No disturbance to normal activities in progress, small work sites
    • No vibration
    • No waste

    Applications of the Uretek solution for filling underground cavities

    Underground cavities and crawl spaces

    • Complete filling and tensioning of underground cavities.

      In the presence of cavities in the subsoil, an unexpected failure of the cavity walls caused by natural agents or surface pressure would lead to subsidence of the soil, with consequent distress for the structures above.

    Unused conduits or pipes

    Unused basements/tunnels

    • Need to make underground conduits or pipes inert

    Lightening of the road or railway embankment

    • To avoid subsidence

    See how we have resolved issues 


    We are close to you and we work wherever in the world our professionalism is needed.
    We are familiar with your area and bring with us multinational experience.

    In 30 years of experience,
    we have completed more than 55,000 projects.