1. Effective soil stabilization and reinforcement – polymer injections in engineering practice

Dynamic technological development in the field of building materials chemistry opens up new opportunities for introducing innovative technological solutions. The same applies to geotechnics. The ground, as an integral part of every building structure, is subject to various processes throughout the entire life cycle of the structure – changes in the groundwater level, settlement resulting, for example, from construction errors or increased loads, frost cycles, or soil erosion. These phenomena can lead to structural deformation, excessive settlement, cracking, and other damage.
To counteract this, work is being carried out to strengthen the ground. In classic methods, such as compaction, DSM, and jet grouting, mainly cement- or silicate-based materials are used. Mineral materials work well in many applications, but they also have significant technological limitations:
they are sensitive to the presence of water in the ground, especially flowing water,
they have a relatively long setting time,
too high pressure cannot be used during their application – they fill larger voids in the ground well, but do not penetrate deeply into its structure.
Technologies based on mineral materials are complemented by a method of soil reinforcement using polymer injections. In this technology, polymer resin, most often highly modified polyurethane resin, is injected into the soil under pressure. Its advantage is its ability to penetrate the soil structure and form a resin-soil conglomerate with high compressive strength.
The material is fed by a two-component injection pump through injection lances of appropriate length. An additional advantage is the very short reaction time – the resin sets within several dozen seconds (this time can be adjusted), and the material itself remains insensitive to the presence of water in the soil, even under conditions of water flow.

2. Polymer injections as an alternative to traditional soil reinforcement methods in tunnel construction

The dynamic development of technology in the field of building materials chemistry creates new opportunities for introducing innovative solutions in geotechnics. In tunnel construction, there is a wide range of problems related to sealing and soil stabilization. In classic methods, such as compaction or jet grouting, cement- or silicate-based materials are most often used. Although mineral materials are used in many projects, they also have significant technological limitations – they are sensitive to the presence of water in the ground, especially flowing water, and are characterized by a relatively long setting time and limited possibility of using high pressure during injection.
Polymer injections complement technologies based on mineral materials. In this method, polymer resin, most often heavily modified polyurethane resin, is injected into the ground under pressure. This material penetrates the soil structure, creating a resin-soil conglomerate with high compressive strength. The injection is carried out using a two-component pump through injection lances of appropriate length. An additional advantage of this technology is its very short reaction time – the resin sets within several dozen seconds (the setting time can be adjusted) and remains insensitive to the presence of water in the soil, even under conditions of water flow.
The use of resins in injection works during tunnel construction significantly reduces the time needed to complete the works, thus reducing investment costs and increasing the safety of the construction process.

Graduate of Wrocław University of Technology – Faculty of Civil Engineering, Institute of Geotechnics, and Wrocław University of Economics – Faculty of Management. A manager with many years of professional experience at MC-Bauchemie. For over thirty years, he has been actively involved in the Polish market in the field of repair, reinforcement, and protection technologies for reinforced concrete structures. His main areas of interest include infrastructure facilities, civil engineering, hydrotechnology, and reinforced concrete energy facilities. He currently focuses on the coordination and development of injection technologies, with particular emphasis on methods of injection reinforcement and sealing of construction soils using polymer materials.