This paper contains the results of fire resistance calculation of reinforced concrete columns with advanced calculation methods.
For columns that are tested unloaded, determine the cross-sectional temperature distribution and values of temperature in reinforcement. The fire resistance of columns that have been tested without load is determined according to temperature measurements, with calculation methods according to the requirements of DBN B.1.1-7 andDBN B.1.2-7.
According to the tabulated method, the fire resistance of reinforced concrete columns is determined by geometric parameters such as cross-section width, axis distance of the reinforcement, amount of reinforcement, length or height of the element, load level during the fire exposure, heating conditions during the fire exposure (number of fire exposed sides).
Accidental combination of actions during the fire situation consists of characteristic values of permanent and variable long-term actions taking into account the safety factor for the consequence class of the object (CC2) and the type of design situation (accidental).
Thermal analysis of the column was performed under conditions of the standard fire exposure. In such conditions it was assumed that the column is exposed to fire with four sides for 120 minutes that corresponds to the required fire resistance class R120.
The thermal state of the column was determined using transient thermal models that take into account radiation-convective heat transfer in the ambient from the heat source to the structural surface, convective heat transfer in the structure, radiation-convective heat exchange from the structure to the ambient environment.
The residual load-bearing capacity of the reinforced concrete column after the fire exposure was calculated with the reduced cross-section determined using zone method in accordance with the requirements of DSTU-N B B.2.6-197 and DSTU-N B EN 1992-1-2.
The fire resistance period of columns for the load-bearing criterion was determined on the basis of the results of of thermal and static analysis.
The performance of timber-framed load-bearing gypsum plasterboard walls subjected to two-sided fire exposure
