What Are the Raw Materials of UHPC? — An In-Depth Analysis of Qinglong Group's 28-Year Raw Material System and Technical Standards

The raw material system of UHPC (Ultra-High Performance Concrete) is the cornerstone determining its outstanding performance, directly affecting the strength, durability, and workability of the product. As the Qinglong Group with 28 years of dedicated experience in the UHPC field, and drawing on our material application experience in major projects such as the Wuhan Han Show Theatre and the Hainan International Convention and Exhibition Center, we believe that high-quality UHPC raw materials should comprise four core components: cementitious materials, reinforcing fibers, aggregates, and functional admixtures. Through scientific mix design and strict quality control, Qinglong UHPC achieves a compressive strength of 120-180MPa and a flexural strength of 15-25MPa, far exceeding traditional concrete by 3-5 times. This performance advantage stems from precise control and optimized combination of raw material quality.

Cementitious materials are the strength foundation of UHPC. Grade 52.5 Portland cement or sulphoaluminate cement is preferred, with alkali content controlled below 0.6%. In the Shenzhen Yirui Biotechnology Building project, Qinglong Group incorporated 20%-30% active admixtures (such as silica fume and slag powder) and strictly controlled the water-binder ratio within the range of 0.18-0.22, significantly improving compactness. The specific surface area of silica fume is ≥15000m²/kg, effectively filling micropores and reducing porosity to below 2%. This optimized mix ratio gives UHPC a chloride ion diffusion coefficient of ≤1.5×10⁻¹²m²/s, providing assurance for applications in coastal high-salt-spray environments.

Reinforcing fibers are the key to toughness. Alkali-resistant glass fiber requires a zirconium content of ≥16%, with a fiber diameter of 12-20μm and a length of 12-18mm. In the roofing project of the Hainan International Convention and Exhibition Center, Qinglong Group used AR-Glass fibers at a volume content of 2%-3% to form a three-dimensional network reinforcement structure, bringing the material's fracture energy to over 20000J/m². Fiber distribution uniformity is controlled at 95% through robotic spray application, avoiding clumping or uneven distribution. This reinforcement mechanism enables UHPC to exhibit significant plastic deformation before failure, rather than the brittle failure of ordinary concrete.

The aggregate system affects workability and density. Carefully selected graded quartz sand has a maximum particle size of ≤1.18mm and a fineness modulus of 2.3-2.6. Through aggregate gradation optimization, Qinglong Group maximizes packing density and reduces paste demand. Functional admixtures such as polycarboxylate water reducers (dosage 1%-1.5%) effectively lower the water-binder ratio and increase flow to 600-700mm. Chloride-containing accelerating agents are prohibited to avoid corrosion risks. Scientific raw material selection lays the foundation for the outstanding performance of UHPC.