EXPERIMENTAL JUSTIFICATION OF THE PARAMETERS OF THE SOIL FOUNDATION MODELOF LARGE-SIZE SLAB FOUNDATIONS OF MULTI-STORY BUILDINGS

In practice, the model of a linearly deformed layer of finite distribution capacity is the most widespread. The possibility of using this model for slab foundations should be confirmed by calculations with a scientific and technical justification of the accepted soil base model and its parameters. Based on observations of subsidence during the construction of a 16-story building on a slab foundation, the use of a model of the soil base in the form of a linearly deformed layer of finite distribution capacity and its parameters is demonstrated. A comparison of the measured and calculated values of the base deformation was made. The object of the study is the ground base and foundation of a 16-story residential building with an underground floor and a parking lot. During the construction, the subsidence of the building was monitored by the method of high-precision leveling of the II class. With the help of the SOFiSTiK software complex, modeling and calculation of the "foundation - foundation - building" system was performed. The soil base model is adopted as a linearly deformed layer of finite distributive capacity. The strength of the layer was limited by the size of the compressible layer. For the soil massif, the boundary conditions in the plan were adopted so that the influence of elm restrictions was minimal. The width of the model was initially set so that the distribution of compressive stresses along the depth was at an angle of distribution α=45º to the vertical from the edges of the loaded foundation. During further modeling, the distribution angle α was changed to 25º. The numerical calculation was performed using the finite element method, which is based on the solution of the theory of elasticity using the SOFiSTiK software calculation complex for the first and second groups of limit states. The possibility of applying the model of the soil base in the form of a linearly deformed layer of finite width for predicting the deformations of the building on a large-sized slab foundation based. It was established that the nature of the development of deformations determined by the calculation for the angles of distribution α=45º and α=25º is proportional to the nature of the development of subsidence determined during field observations. It has been demonstrated that the angle of distribution α=25º is optimal for modeling the soil massif of the foundation, ensuring the reliability of moment stress values.