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　　The specification requirements for tunnel fireproof boards must meet the following core standards and technical points:

　　1、Fire performance requirements

　　Fire resistance limit:It must meet the A-level non combustible material standard,with a fire resistance time of at least 2-3 hours(adjusted according to the tunnel type).

　　Thermal insulation:The thermal conductivity should be≤0.12W/(m·K)to ensure controllable back temperature during a fire.

　　Low smoke and non-toxic:When burned,it produces less smoke and does not release harmful substances such as formaldehyde or radiation.

　　2、Physical performance

　　Compressive strength:It needs to withstand a pressure of≥0.5MPa to avoid deformation or fragmentation.

　　Density control:generally≤500kg/m3,balancing lightweight and structural stability.

　　Environmental adaptability:resistant to extreme temperatures(-40℃~120℃),resistant to freeze-thaw cycles(50 tests),water absorption rate≤10%.

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　　3、Installation and Construction

　　Bonding strength:The bonding strength with the tunnel wall is≥0.1MPa to prevent detachment.

　　Construction convenience:Supports cutting and drilling,with errors that meet assembly requirements.

　　4、Testing standards

　　GB28376-2012:It covers 18 technical requirements such as resistance to moisture and heat,salt spray,etc.The fire resistance performance needs to pass BZ,HC or RABT temperature rise curve tests.

　　GA/T714-2007:The criterion for determining failure is that the temperature of the bottom surface of the concrete slab is greater than 380℃or the temperature of the steel reinforcement is greater than 250℃.

　　5、Special scenario supplement

　　Seismic requirements:The seismic zone must have the ability to resist deformation,and the composite panel must use metal keel to absorb structural displacement.

　　Noise reduction function:Some tunnels(such as subways)need to take into account sound absorption performance.

　　The above specifications integrate national standards(such as GB28376,GB50016)and industry practices to ensure that fireproof boards effectively protect the safety of tunnel structures in fires.