Evaluation of Fire-Resistance of Strut Reinforced Concrete Structures

Abstract

Ключевые слова: здания и сооружения, железо-бетонные конструкции, неразрушающие испытания, оценка огнестойкости, методика расчета, ресурсо-энергосбережение.

Analytical description of physical and technical parameters of a bending reinforced concrete structure, influencing reinforcement fire resistance

“…The study reveals a mathematical description of the indicators, which take into account the value of concrete thermo-diffusion reduced coefficient, intensity of force tension in working reinforcement and the size of its diameter. Analytical functions (4,6,9) are introduced in this study to take into account these indicators.…”

Composite building structures and their fire resistance: a methodology of resource-saving evaluation

“…where B is the smallest size of rectangular cross sections in a compression flange, mm; J σ0 -is an intensity of strength stress in the cross section of a compression flange (0 -1); α μ3 is a degree of reinforcement of a compression flange; K 2 is an integral index of safety of a compression flange; D bm is thermal diffusion rate of the protective layer of concrete, mm 2 /min; R bn is normative strength of concrete for resistance to axial compression, MPa [7,12,13]. The intensity of strength stress in the cross-section of the compression flange of the composite construction (J σ0 ) coming from a test load for fire-poof capacity, is calculated by conditions (11):…”

Evaluating the load-carrying ability of compressed reinforced concrete elements with heterogeneous strength properties of concrete

“…where N bi -a force taken by compressed concrete of layer i by formula (8). where σ b -the stress in the concrete; ε b -relative deformation of the most compressed face of the element resulting from the reparsing; x -the coordinate of the compressed concrete zone point in question; ; k -the full height of the compressed concrete area resulting from the reparsing; a c and b c -coefficients of exponential function f(ε)= ε E, which describes the shift of the elasticity module from magnitude ε; р -relative deformation of concrete in the chart f the maximum value of the stresses.…”