Scientific approach to fire resistance calculation of reinforced concrete beams and columns

Abstract

Problems related to the fire resistance calculation of reinforced concrete beams and columns from a scientific point of view when using new design standards are considered. The first problem is the insufficient development of improved calculation methods, exactly their absence. Only basic principles and requirements are formulated for them. This article presents the principles and sequence of calculation. The second problem is the lack of an accurate mathematical nonlinear compression model of the stress-strain diagram for concrete. The article explains the imperfection of the existing one, the need to create a new model and presents the basic requirements that such a mathematical model must meet. The third problem of the discussed ones is the erroneous values of the relative ultimate deformation of concrete. The principle of formation of values of relative limiting deformation of concrete is specified and proceeding from it the additional requirement for mathematical nonlinear model of compression of the diagram of stress - strain for concrete is specified.

Simulation of shear strengthening fire-exposure high strength lightweight reinforced concrete beams using basalt fiber-reinforced polymer grid and engineered cementitious composites jacket

“…Many contemporary design standards have been established, such as ACI 216.1 [1], AS 3600 [2], BS 8110-2 [3], to provide dependable advice for analyzing and designing concrete buildings that are exposed to fire [4,5], among others. These standards have been formulated depended on experimental data obtained from controlled fire tests [6]. During a fire, concrete is subjected to elevated temperatures, which greatly diminishes its ability to withstand compression and deformation, particularly when subjected to temperatures exceeding 550°C.…”