EVALUATION METHOD FOR FIRE-RESISTANCE OF REINFORCED CONCRETE GIRDER STRUCTURE OF BUILDING Russian patent published in 2017 - IPC G01N25/50 

FIELD: fire safety.

SUBSTANCE: testing of reinforced concrete girder structure of the building is carried out without destruction, according to the complex of single quality indexes by evaluation of their value with the help of statistical control. For these purposes, geometrical dimensions of the girder structure (slab, girder), the diagram of the unsafe cross section heating under the fire conditions, arrangement of steel in the section, its laying depth and its fire protection level, the thermal diffusion index of concrete, the magnitude of test load on the girder structure and the stress intensity in the rods of lateral working reinforcement. The fire resistance limit of the girder structure is determined according to the factor of bearing-capacity failure (R), using the analytical equation (1); according to the factor of thermal insulating capacity (J) loss - according to the power function (2). In describing the process of reinforced concrete girder structure resistance to the fire effect of a standard fire, it is taken into account the fire protection level of the stell C, cm, the intensity of its stress Jcσ and the thermal diffusion of concrete indicator Bbm, mm²/min, and the features of the girder structure reinforcing and statistical diagram of its work as well.

EFFECT: provision of possibility for definition of the actual fire resistance of the reinforced girder structure without field fire exposure, improvement of accuracy of statistical control quality and non-destructive testing.

8 cl, 2 dwg