Determination of the deformation modulus of soil-cement by laboratory methods during construction site investigations

Summary. In the modern construction of multi-storey buildings, pile foundations are becoming increasingly common in difficult conditions of weak soils. Modern engineers face the difficult task of choosing design solutions that not only meet modern construction requirements but also ensure economic feasibility in dense urban development and complex geology. One of the most promising methods of solving this problem is the use of soil-cement elements to reinforce the foundation as an alternative to pile foundations. This approach can significantly reduce the cost of constructing foundations and reduce the labor intensity of the processes associated with design and construction due to the simple technology of such elements. The main purpose of the study is to evaluate the physical and mechanical properties of soil cement produced by the drilling and mixing method, as well as to determine its deformation modulus during the construction of a residential building. To determine the modulus of deformation of the reinforced base of a multi-storey residential building, data from engineering and geological surveys were obtained. The geological structure of the territory to the explored depth is based on loams, sandy loams and clays. According to the data obtained, the prolific soil properties were revealed at a depth of 7.5 to 8.4 meters. To achieve this goal, a number of preparatory works were carried out, including the preparation of equipment, in particular the MII-100 device for measuring bending strength with a working range of measurements up to 100 kgf/cm2, as well as the manufacture of prism samples measuring 40x40x160 for laboratory tests. The prepared samples made it possible to implement a full cycle of experimental studies, including strength and deformation tests. The results obtained allowed us to conclude that the deformation modulus of the base reinforced with soil-cement elements increases by 15 times compared to conventional soils. This is an important argument in favor of using soil cement in weak clay soils. The study confirms the high efficiency of using soil cement to strengthen foundations with a methodology for checking the deformation modulus during surveys. Particularly noteworthy is the practical significance of the work, which is to increase the reliability and durability of multi-story buildings. This method can be successfully implemented in modern construction, which will reduce material costs, optimize technological processes and improve the performance of buildings and structures.