Can UHPC Curtain Wall Panels Achieve a Class A Fire Rating? Material Properties and Construction Verification

The fire resistance rating of UHPC curtain wall panels naturally possesses Class A non-combustible properties. The core materials are inorganic non-combustible components, with combustion performance reaching Class A1 as verified by authoritative testing. Through structural optimization, fire integrity and thermal insulation of ≥1.5h can be achieved, fully meeting the Class A fire protection requirements for high-rise building curtain walls under the "Code for Fire Protection Design of Buildings". Qinglong's UHPC curtain wall panels have passed multiple tests and project verifications, with fire resistance ratings consistently meeting standards.

Class A non-combustible properties of the material itself: an inherent fire protection advantage. The main components of UHPC are low-alkali cement, quartz sand, and steel fibers/alkali-resistant glass fibers, all of which are inorganic non-combustible materials containing no organic combustible components. According to the "Classification for Burning Behavior of Building Materials and Products" (GB 8624-2012), they naturally meet the Class A1 non-combustible standard. Tested by the National Fire Product Quality Supervision and Inspection Center, Qinglong's UHPC curtain wall panels achieve Class A1 combustion performance with an oxygen index of ≥60%, no burning drips, and no toxic smoke release. In high-temperature environments (≤600°C), component strength decreases somewhat, but there is no collapse or fall-off, and structural integrity is maintained. The UHPC curtain wall of the Wuhan Hanxiu Theater, in a fire simulation test, withstood 1 hour of burning at 1000°C without open flame or large-area detachment, verifying its non-combustible properties; the UHPC exterior wall panels of a high-rise project were tested with a fire resistance limit of 1.8h, meeting high-rise building fire wall requirements.

Structural optimization improves fire integrity and thermal insulation. A single UHPC curtain wall panel has limited fire insulation performance, which needs to be enhanced through structural design optimization: 1) gaps between the curtain wall and the main structure are filled with fire-resistant rock wool (thickness ≥100mm, density ≥120kg/m³), which is non-combustible with low thermal conductivity, effectively blocking flame and heat transfer; 2) fire-resistant sealant (fire resistance limit ≥1.5h) is applied at joints to prevent flames from penetrating through gaps; 3) for high-rise or super high-rise buildings, a fire board (such as calcium silicate board, thickness ≥12mm) is added on the inner side of the UHPC curtain wall, forming a composite fire protection structure of "UHPC panel + air layer + fire board" to enhance insulation. In the Shenzhen Pingshan High-tech Zone Comprehensive Service Center project, Qinglong adopted this composite structure, with both the fire integrity and thermal insulation of the UHPC curtain wall reaching 2.0h, meeting the fire protection requirements of super high-rise buildings; the UHPC fire wall of a public building was tested with a fire resistance limit of 2.5h, far exceeding the 1.5h required by the code.

Testing and project verification of fire resistance ratings: authoritative data support. Every batch of Qinglong's UHPC curtain wall panels is sent to authoritative third-party institutions for testing, covering combustion performance, fire integrity, thermal insulation, smoke toxicity, and other items, with all indicators meeting Class A standards. The UHPC curtain wall of a residential building project was tested with Class A1 combustion performance, 1.6h fire integrity, and 1.5h thermal insulation, and smoothly passed fire acceptance; the UHPC public art components of the Shanghai Astronomy Museum achieved a Class A1 fire rating, meeting the strict fire protection requirements of science venues. In addition, the "General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components", which Qinglong participated in drafting, clearly stipulates that the combustion performance of UHPC non-load-bearing components should reach Class A1, further establishing the fire resistance rating standard for UHPC curtain wall panels.

Precautions affecting fire resistance ratings. Avoid applying combustible coatings (such as certain oil-based paints) to the surface of UHPC curtain wall panels, as this will lower the fire resistance rating; connectors should be made of non-combustible materials (such as stainless steel), and combustible plastic connectors should be avoided; fire protection structures (such as fire-resistant rock wool and fire-resistant sealant) must not be damaged during construction, otherwise weak points in fire protection will be created. During construction, Qinglong conducts special acceptance inspections of fire protection structures to ensure that construction quality does not affect fire performance; complete fire testing reports and fire acceptance documents are provided to help customers smoothly pass fire review.

The fire resistance rating of UHPC curtain wall panels naturally reaches Class A, and fire integrity and thermal insulation can be further improved through structural optimization, fully meeting the fire protection requirements of all types of buildings. With the inherent non-combustible advantage of the material, scientific structural design, and authoritative testing verification, Qinglong provides fire-compliant UHPC curtain wall panels for every project. For owners and designers, the fire resistance rating is a key safety indicator in curtain wall material selection; choosing UHPC curtain wall panels with Class A fire performance can effectively improve building fire safety, and Qinglong safeguards building fire protection with professional technology.