Self-Locking Elements in Pipe-Concrete Columns

Abstract

The study of samples of tubular concrete columns of circular cross-section (TBC) under local compression with initial eccentricity was carried out. To increase the strength of non-centrally compressed TBCs, steel self-locking elements were placed in the concrete core. They were laid in three rows in the space between the upper end of the freshly laid concrete and the inner surface of the steel pipe. Moreover, the lower and upper layers of self-locking elements were made in the form of partially truncated tetrahedra  btained by cutting cubes with planes passing through the middle of their edges into two equal parts. A layer of cubes was placed between the layers of truncated tetrahedra in such a way that all the elements were in close contact with each other with their faces. The experiments performed have confirmed the ability of self-locking structures due to their high rigidity to redistribute concentrated loads transmitted through them more evenly. It is shown that the selection of the rational geometry of the structural elements of self-locking elements and the conditions of their interaction with each other can be an effective method of increasing the rigidity of certain sections of structures. The use of a structure of 3 layers of self-sealing elements significantly changed the nature of deformation and destruction of TBK samples, which led to an increase in the strength of the studied samples by an average of 11%.