Research on the impact of new construction on the stress-strain state of the soil base foun-dations of existing buildings

Summary. The trends of the modern stage of housing development, which is accompanied by an increase in the density of development of historically formed areas of large cities, are analyzed. Engineering problems arise that are associated with the use of underground space and lead to a change in the stress-strain state of existing buildings. Many buildings, next to which construction is underway, have shallow foundations. The construction of new foundations, excavation of pits for the arrangement of underground space disrupt the balance of the stress-strain state of the soil base and, in most cases, have a negative impact on existing building structures. Research conducted in this area indicates the significant relevance of this topic. An important role in this is played by a comprehensive system of geotechnical monitoring of the state of the surrounding development at different stages of new construction. The practice of construction in dense development with the presence of observations of the movements of existing buildings has shown the possibility of additional settlements and damage to above-ground structures, which indicates the lack of justification for the adopted design decisions. When analyzing the stress-strain state of the “base - foundation - above-ground structures” system, it is necessary to take into account not only the physical and mechanical parameters of the soils, hydrogeological conditions, loads, but also to pay significant attention to the technology of work and the sequence of their execution. A study of the patterns of the influence of new construction on the stress-strain state of the existing building has been conducted. Geotechnical monitoring data are presented and compared with the results of numerical modeling. Numerical modeling was performed in two versions: in combination and without a protective screen of small-diameter piles. The soil mass was modeled using the Hardening Soil Model. The possibility of stabilizing the stress-strain state of the soil mass during the performance of underground cycle works has been shown. A sequence of designing buildings with underground space is proposed, which allows achieving the effect of minimizing the impact of new construction on additional subsidence of the foundations of neighboring buildings