Design features of strengthening soil foundations of buildings and structures by reinforcing soil-cement columns

An increase in the pace of construction and the development of sites with weak soil foundations entails the development of the geotechnical sphere and construction technologies. This article discusses promising methods of strengthening the base by reinforcing vertical soil-cement columns: Jet-cementing and deep mixing of soils, which are widely used both in our country and in foreign countries. The main methods of assigning design parameters are considered, and the available generalizations and assumptions in the existing regulatory framework are highlighted. These methods include: the method of SP 22.13330 according to the principles of natural soil foundations; methodology SP 24.13330 as for a massive foundation; modeling by the finite element method using software systems. An analysis of the existing methods for calculating the reinforced foundation by these methods made it possible to identify the areas of necessary research aimed at improving the existing methods of designing and assigning design parameters. The existing methods of quality control of the work performed the foundation soils by reinforcing vertical soil-cement columns are considered. The main criteria and methods for assessing the quality of amplification, reflected in the regulatory documentation, are shown. The experience of designing reinforcement of soil foundations with soil-cement columns and control of reinforcement parameters is presented. Conclusions are formulated and specific tasks for further research are set to improve such methods of strengthening the soil mass, as methods of deep soil mixing and Jet cementation.

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