METHOD FOR EVALUATING FIRE RESISTANCE OF REINFORCED CONCRETE SLAB WITH PINCHED CONTOUR Russian patent published in 2018 - IPC G01N25/50 

FIELD: fire safety.

SUBSTANCE: invention relates to the field of fire safety of buildings and structures and can be used to classify reinforced concrete slabs with pinched contour. Essence of the invention lies in the fact that the test of reinforced concrete slabs is carried out without destruction, using a complex of individual quality indicators, estimating their value using statistical control. For this purpose, the geometrical dimensions of the reinforced concrete slab, the heating pattern of the design cross section under fire conditions, the placement of the reinforcement in the cross section, the depth of embedding and the degree of its fire protection, the indicator of thermal diffusion of concrete, the value of the test load on a concrete slab with pinching along the contour and the intensity of the stress in the rods of the working reinforcement are determined. Fire resistance limit of reinforced concrete slab is determined by the sign of loss of bearing capacity F_U(R), using analytical equation (1). When describing the process of resistance of a reinforced concrete slab to the fire impact of a standard fire, the following parameters are taken into account: the degree of fire protection of the reinforcement C, cm, the intensity of its stress J_σs (within 0.1–1.0) and the index of thermal diffusion of concrete D_BT, mm²/min as well as features of the reinforcement of reinforced concrete slabs and static scheme of its operation.

EFFECT: providing the possibility of determining the design fire resistance of a reinforced concrete slab without full-scale fire exposure and increasing the reliability of statistical quality control and non-destructive testing.

11 cl, 4 dwg