СОПРОТИВЛЕНИЕ КОРОТКИХ БЕТОННЫХ ЭЛЕМЕНТОВ ВНЕЦЕНТРЕННОМУ СЖАТИЮ С БОЛЬШИМИ ЭКСЦЕНТРИСИТЕТАМИ

Abstract

The paper considers the methodology of calculation of short concrete elements under eccentric compression with large eccentricities. The analysis of normative methods of calculation of eccentrically-compressed elements has been carried out and the reasons of discrepancy of calculated values with experimental ones for concretes of class B15-B60 have been established. The equations of equilibrium conditions, deformations, physical laws and geometrical relations developed by the author on the basis of the results analysis of numerous experimental laboratory researches of concrete and reinforced concrete elements under central and eccentric compression and bending are presented. The numerical investigation of the bearing capacity of eccentrically compressed elements with large eccentricities (from 0.167 to 0.45h) and of concrete strength from B15 to B60 MPa has been made in comparison with the data of other researches and with the normative procedure. The results showed that the bearing capacity of the majority of calculated elements compared to the normative method turned out to be 20-25 % higher, and transverse stiffness by 30-35 %. It has been established that the developed solution gives qualitatively more correct and quantitatively more exact results in the whole range of eccentricities and concrete strength than those obtained by means of normative literature, realizing a differentiated approach to different concrete strengths. The analytical dependences of the developed method, obtained in closed form, can be recommended for use in design practice.