Blashchuk N. Joint operation of existing foundation and piles during strengthening

The purpose of the thesis is to evaluate the stress and strain state (SSS) of foundation, strengthened by piles of strip shallow foundation and also to design the approach of its calculation. By means of physical model engineering on small-scale models, there have been established the principal consistencies of part of a load relation, that perceives the existing foundation as grillage, from geometric characteristics with enhanced foundation and technologies of piles construction (through the foundation body or remote piles). There has been done the numerous modeling by means of FEM systems "existent foundation - enhanced piles - base" and "piles - grillage - base", according to which, there has been analyzed the impact on SSS base of piles not only with the help of its geometric characteristics, but also taking into account its physical and mechanical properties of ground and kinds of piles (they are established with or without extract of ground). By means of correlation analysis of data received, there have been proposed the robust dependences, that allow to take into account the principle geometric characteristics and physical and mechanical properties to evaluate the stress, received by grillage in the system as "piles - grillage - base" during new construction with enhanced piles. For the first time, there has been demonstrated the calculation procedure of accepted load on strip shallow foundation, strengthened by piles, whereby it allows to consider the work of grillage, taking into account the most powerful factors. Such approach is adapted for modern strip pile foundation. Key words: strengthening, strip shallow foundation, piles, grillage, system "pile-grillage-base".