Stress-strain state of the "combined tower-reinforced concrete foundation-foundation soil" system for high-rise structures

Abstract

© The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/). The aim of the work was to evaluate the effectiveness of the "combined tower-reinforced concrete foundation-foundation soil" system for high-rise structures on the example of a wind power plant (wind turbine) with a capacity of 1.5-2.0 MW using computer modeling in the PC "Ansys". Thus, under the combined tower the article refers to a high-rise building, consisting of two parts: the lower composite, the upper - in the form of a thin-walled core-shell closed profile. In both cases, the shell is a pipe with a weak taper. As an analogue, the VEU considered in foreign literature is adopted: the radius of the rotor is R=41 m, the height to the axis of the wind wheel is zhub =80 m, the shell is made of high-strength C355 steel and unlike the analog in this work the cavity of the tower lower part to a height of 20 m was filled with B60 class concrete. The modeling took into account the spatial work of the elements of the structural system and the physical nonlinearity of the materials from which they are made. At the same time, the Mises strength theory was used for steel, the Williams - Varnake theory - for concrete, and the Drukker - Prager theory - for the foundation soil. Comparison of the calculation results with the analogue showed that the destructive load of the tower increased by 37% due to filling the lower part of it with concrete, which indicates the effectiveness of the proposed solution. In this case, the destruction of the tower with a concrete core and without it occurred from the loss of steel shell local stability at the level of the tower junction with the foundation (with a compressed zone).