Fire resistance limit refers to the time it takes for a building component, accessory, or structure to lose its fire resistance stability, fire integrity, or fire insulation properties under standard fire resistance test conditions, starting from exposure to fire.
Fire resistance performance refers to the ability of a building component, accessory, or structure to meet the stability, integrity, and/or insulation requirements of a standard fire resistance test within a certain timeframe. Fire resistance stability refers to the ability of load-bearing components to resist collapse; fire integrity refers to the ability of partition components to prevent the penetration of flames and smoke; and fire insulation refers to the ability of partition components to limit the temperature rise of their unexposed surfaces.
The main factors affecting the fire resistance limit of building components include the material's inherent combustion performance and thermal conductivity, the component's cross-sectional dimensions and protective layer thickness, the component's structural characteristics and connection methods, the construction method between the material and the structure, the test conditions specified in the standard, the material's aging performance, and the type of fire and environmental requirements.
For structural systems, the overall fire resistance performance assessment requires comprehensive consideration of the fire resistance performance of all individual components, such as columns, beams, floors, and walls. Among them, load-bearing components must meet the requirements of fire resistance stability, partition components must meet the requirements of fire resistance integrity and heat insulation, and load-bearing partition components must meet all three requirements at the same time.
