Influence of long-term exposure to loads on the annular sections’ strength and rigidness

Abstract

A numerical experiment was carried out to study rigidity, critical force, and bearing capacity of reinforced concrete racks with annular section under short-term and long-term loading. The effect of long-term loading was estimated in the numerical experiment by changing the coefficient φl from 1 to 1.8 times 0.2, as well as the modulus of deformations Eb,τ, taking into account the operating conditions (W = 40-75%). At the same time, the external load on the rack N was taken in the experiments as a multiple of the critical force Ncr from 0.2 to 1.0, and the relative eccentricity δe of the load application varied from 0.15 to 1.35, which made it possible to estimate the stress state of the struts in an extended range of possible loadings. The results obtained made it possible to identify qualitative and quantitative regularities of rigidity changes, critical force and bearing capacity of annular struts during short-term and long-term load application.