Determining bearing capacity of T-shaped profile by using simplified deformation diagrams of materials

Abstract

In modern standards of projecting iron-concrete construction (p.3.1.6. [1]) with making checking calculations or close to it, allowed to use simplified two-line diagram of concrete’s deformation. In this article was looked the method of definition iron-concrete beam's bearing capacity of T-shape profile by using simplified deformation diagrams of materials. The simplified diagrams of concrete’s deformation and reinforcing steel are accepted in accordance with the basic requirements [1]. The strained-deformed state of normal profile is considered depending on work’s stage stretched and compressed fittings, the location of the neutral axis at a constant geometric cross profile in determining the bearing capacity. The criterion of destruction is the achievement of limiting deformations in stretched fittings or in compressed concrete. The algorithm of calculation involves the following operations.Determination of the location of the neutral axis with the assumption that the fittings in the compressed and stretched zone works at the stage of flow, and deformations in the concrete reaches the limit values. After that check all 12 possible variants of occurrence of various strained-deformed profile’s states that can arise in the specific conditions by method of gradual selection. This allows to get simple, from a mathematical point of view, engineering solutions. This approach allows to understand the stages of the construction’s work under the influence of the load, to evaluate the efficiency of the using fittings in the compressed and stretched zones of iron-concrete, to understand the basis of rational construction’s desing, therefore, can widely use as in engineering practice as in the training process in the teaching of design engineers.