**8. Conclusion**

PU grouting is performed in order to achieve improvement of physical and mechanical properties of the rock, soil, or building material in the construction. It requires experience and complex knowledge from various fields like geology, hydrogeology, structural geology, rock and soil mechanics, geotechnics, mining, underground constructions, construction of foundations, structural stability, defects of constructions and their repair, chemistry of the grouting material, grouting technique (pumps, packers) and etc. Grouting technologies represent an effective technology of solving of various kinds of problems in mining, building industry and geotechnics practice.
