METHOD OF DETERMINING FIRE RESISTANCE OF PIPE CONCRETE COLUMN OF BUILDING Russian patent published in 2019 - IPC G01N33/38 

FIELD: rescue service; fire fighting means.

SUBSTANCE: invention relates to the field of fire safety of buildings with reference to the classification of pipe-concrete columns based on their resistance to fire. Method comprises performance of technical inspection, establishment of type of concrete column, identification of conditions for its support and attachment, determining the time limit state on the basis of the loss of bearing capacity of the column under the test load under conditions of standard fire action, performance of evaluation tests without destruction by a set of single quality indicators of the string, in which technical inspection is accompanied by instrumental measurements of geometric dimensions of the column and its hazardous section, concrete and steel areas in dangerous section are installed, humidity and density of concrete in natural state, determining the concrete thermal diffusion indices, determining compression concrete ultimate resistance, intensity value of the stresses in the dangerous section, wherein determining the fire resistance of a pipe concrete column made from a metal pipe filled with concrete, wherein additionally determining the level of responsibility of the column for the purpose, determining critical force, rigidity of pipe concrete column and effect of column deflection on bending moment of longitudinal force, degree of reinforcement of column cross-section by metal pipe, determining resistance limit of compression of pipe metal, reduced thickness of pipe metal and time of resistance to fire action of metal pipe, unfilled with concrete, calculating duration of fire protection of concrete pipe metal and fire resistance of pipe concrete string from beginning of standard fire action to loss of bearing capacity (F_ur, min), which is determined using a given analytical expression.

EFFECT: enabling determination of the pipe concrete column fire resistance without natural fire action and high reliability of statistical quality control and non-destructive tests.

9 cl, 1 ex, 2 dwg