STEEL STRUCTURES FIRE RESISTANCE ASSESSMENT UNDER STANDARDIZED FIRE TEMPERATURE REGIMES

Purpose. Fire development model application field to assess fire resistance of steel basic structures, taking into account the terms of use of buildings and structures was determined. Methods. The regulatory sources were analyzed by the authors; calculation of steel structures heating with and without fire protection were carried out under the conditions of a standard temperature regime of a fire and a regime of hydrocarbons combustion using the Ansys software package; the calculations were compared with experimental data. Findings. The conducted research to assess steel structures fire resistance under the conditions of a standard temperature fire regime and hydrocarbons combustion regime demonstrated the possibility of calculating their heating using the Ansys software package. It has been established that the fire resistance limit for the loss of steel structures bearing capacity without fire protection at a standard temperature regime is 2 times higher than at a hydrocarbon temperature regime, and with fire protection made of cement-sand plaster or Newspray coating - 1.2-1.3 times. Research application field. The calculated values of the limits of steel basic structures fire resistance with fire protection made of cement-sand plaster or Newspray coating for a standard fire temperature regime can be used in the design and reconstruction of residential, public and office buildings. When designing buildings and structures of oil and gas, petrochemical enterprises, offshore fixed platforms for oil and gas production, the calculations outcomes for steel structures fire resistance under conditions of a hydrocarbon temperature regime should be used. Conclusions. The possibility of calculating the actual limit of fire resistance of unprotected steel building structures and structures with fire protection under the conditions of a standard fire temperature regime and hydrocarbons combustion regime with using the Ansys software package was determined. The resulting nomograms of steel structures fire resistance with fire protection made of cement-sand plaster and the Newspray coating may be used to design passive fire protection systems at construction sites, taking into account the standardized fire temperature regimes, depending on the terms of structures use.