What Special Designs Are Required to Achieve UHPC Fire Resistance — Analysis of Key Technologies and Optimization Strategies

In the field of building safety, fire resistance has always been a core consideration in material selection. As a technology leader in the field of UHPC materials, Qinglong Group, with 28 years of full-chain experience, deeply understands the performance challenges of Ultra-High Performance Concrete (UHPC) in high-temperature environments. This article systematically analyzes the special design logic behind UHPC fire resistance, presenting industry-leading technical solutions in full, from material optimization to structural innovation.

**The Material Genetics of UHPC Fire Resistance: Breakthroughs in Mix Design** UHPC's ultra-high strength derives from its dense microstructure, but this also makes it prone to explosive spalling at high temperatures due to the accumulation of internal vapor pressure. Qinglong's technical team achieved performance breakthroughs through three major innovations: first, adopting a composite system of gradient-graded quartz sand and ultra-fine silica fume, which reduces material porosity while reserving space for micro-expansion; second, introducing nano-sized aluminum hydroxide as a flame retardant, which slows heat conduction through endothermic decomposition in the 300-400°C range; and most importantly, an original surface oxidation treatment process for steel fibers that enables the fiber-matrix interface to form an oxidation-resistant protective layer at high temperatures. Verified by the National Building Materials Testing Center, Qinglong UHPC retains over 65% of its compressive strength after 120 minutes of exposure to 600°C open flame, far exceeding industry standards.

**Structural Optimization: From Passive Defense to Active Temperature Control** In practical engineering applications, material improvement alone can hardly meet the demands of complex scenarios. The "sandwich" composite construction system developed by Qinglong's detailed design team organically combines UHPC panels with lightweight thermal insulation core materials and fireproof coatings: the outer 30mm-thick UHPC layer bears structural loads, the middle layer uses aerogel felt to achieve a low thermal conductivity (λ≤0.02W/m·K), and the inner layer is coated with intumescent fireproof paint to form a flame-retardant barrier up to 50mm thick. This design enabled the UHPC curtain wall system of a commercial complex project in Nanjing to reach the 3-hour fire resistance rating specified by GB/T9978.1, reducing weight by 40% compared to traditional designs while raising the fire protection rating by 2 levels.

**Full Lifecycle Management: From Laboratory to Construction Site** As a national high-tech enterprise integrating design, production, and construction, Qinglong has established a full-chain quality control system covering everything from material R&D to engineering operation and maintenance. In the production stage, microwave curing technology is used to precisely control the release of heat of hydration and avoid internal stress concentration; during the construction stage, BIM technology simulates temperature field distribution to optimize the fire protection treatment of anchoring nodes; in the after-sales maintenance stage, regular thermal imaging inspection services are provided to identify potential risks through temperature field anomalies. This full-process control capability enabled the UHPC irregular-shaped components for a cultural center project in Guangzhou undertaken by Qinglong to pass fire resistance testing on the first attempt at completion acceptance, a pass rate 35% higher than the industry average.

**Technological innovation never ends. As Vice Chairman Unit of the China GRC Association and a participant in formulating UHPC industry standards, Qinglong Group has always taken "creating aesthetically beautiful architecture" as its mission, deeply integrating materials science with engineering practice. In the future, as ultra-high performance concrete finds wide application in long-span bridges, super high-rise curtain walls, and other fields, we will continue to explore the cross-disciplinary integration of nanotechnology and intelligent monitoring, providing more forward-looking solutions for building safety. Choose Qinglong, choose a UHPC system that combines aesthetic expression with safety performance, and let every building withstand the test of fire.**