How to improve the fire resistance of U-shaped glass curtain wall?
U-shaped glass curtain wall is favored by architects for its gorgeous appearance, outstanding lighting and exquisite texture. However, complex and beautiful curtain wall design will also have a negative impact on fire safety. Fire blocking belongs to the category of compulsory fire extinguishing, corresponding to automatic fire extinguishing (including sprinklers, detectors, etc.)
Currently widely used, it refers to blocking fire walls, pipe wells, strong and weak bridges, etc. It refers to buildings using fireproof materials (products), especially high-rise buildings, which need to have certain fire-resistant holes or chimney-like cracks that are easily formed during fires to block the fire source from passing through other fire partitions or others. It includes the detailed structure of various penetrations through walls and floors and the treatment of various structural joints.
How to improve the fire resistance limit of curtain walls, extend the fire resistance time, and minimize the losses caused by fire are issues that must be considered in the design and use of curtain walls. However, what kind of structural scheme is reasonable and how long the fire protection time can be cannot be estimated or measured by subjective assumptions. The design must be based on relevant data obtained from relevant experiments.
Regarding the fireproof sealing method of the interlayer joints of the U-shaped glass curtain wall, it is mainly to fill the joints with extruded mineral wool and cover the mineral wool with spray glue to form a high smoke density and high fire resistance system. Its fire resistance is as follows:
1.The total width of the small density of 64kg/m3 is 125%~150% of the gap width, so that the mineral wool in the gap has sufficient pre-compression. On the one hand, it offsets the loose and falling outward expansion force caused by the thermal expansion of the mineral wool in the fire; on the other hand, it makes the mineral wool denser by extrusion. For larger gaps (≥250mm), the tightness between the mineral wool and the floor can be improved by adding angle steel or fasteners.
2. The specially formulated spray glue is carbonized into fine particles in the fire, covered on the mineral wool, and filled in the small holes on the outer surface of the mineral wool, so that the carbonized layer of the spray glue and the mineral wool form a smoke and fireproof belt; this is completely different from the sealing principle of the traditional galvanized steel plate as the support plate. The traditional galvanized steel plate will expand when it encounters fire, resulting in more openings and smoke diffusion.
3. The separation zone of the relevant construction method is fixed on the pad or angle steel independently of the curtain wall structure through the setting of nails. Therefore, even if the lower curtain wall structure is blown away, the isolation zone can still maintain its integrity and prevent the fire from spreading upward.
