What Are the Raw Materials of UHPC and Analysis of Their Characteristics

Amid the wave of innovation in contemporary building materials, ultra-high performance concrete (UHPC) is redefining the boundaries of architecture with its outstanding mechanical properties and design plasticity. As an industry leader with 28 years of deep expertise in UHPC/GRC/GRG/GRP materials, Qinglong Group has witnessed and driven the entire journey of this material from the laboratory to urban landmarks. This article systematically analyzes the core raw material composition of UHPC and its unique properties, providing designers and owners with a professional reference for material selection.

UHPC Raw Material System: Scientific Proportioning of Four Core Components

UHPC's high performance is not the effect of a single material, but the result of the synergistic optimization of multiple components. Its raw material system mainly comprises four categories: cementitious materials, aggregates, fibers, and admixtures, each of which has a critical impact on the final performance. In its 600,000-square-meter annual production capacity at the production base in Nanning, Guangxi, Qinglong Group consistently adheres to the principle of optimal proportioning to ensure the performance stability of every batch of products.

Cementitious Materials: The Foundational Guarantee of Strength and Durability

The cementitious system of UHPC is based on cement, typically Portland cement or sulphoaluminate cement with a strength grade of no less than 42.5, combined with mineral admixtures such as silica fume and fly ash to form a composite cementitious material. The addition of silica fume fills the microscopic pores between cement hydration products, increasing material density by more than 30%, while activated fly ash optimizes paste flowability and reduces hydration heat. The cementitious material proportions determined through more than 2,000 trials by Qinglong's R&D center give the products an impermeability grade of P12 or above, far exceeding traditional concrete standards.

Aggregate System: An Upgrade from "Skeleton" to "Reinforcement"

Unlike ordinary concrete, UHPC adopts a continuously graded fine aggregate system, typically using quartz sand or river sand with a particle size of 0-5mm, with the maximum particle size not exceeding 1/3 of the fiber length to avoid stress concentration. In some high-end projects, steel slag or basalt aggregates are also incorporated, enhancing overall strength through aggregate-paste interface strengthening. In the Century Plaza renovation project on Nanjing East Road, Qinglong innovatively combined light-transmitting quartz sand with UHPC, achieving the dual functions of structural load-bearing and artistic light transmission. The project won the Silver Award at the first AALBORG WHITE Cup UHPC Building Engineering Innovation Award.

Fiber Reinforcement: The Key to Toughness and Crack Resistance

Steel fiber is the "backbone" of UHPC. Micro steel fibers with a diameter of 0.1-0.3mm and a length of 10-20mm are typically used, with a volume dosage generally of 2%-5%. The fibers form a three-dimensional randomly distributed network within the material, effectively arresting crack propagation and giving UHPC an ultimate tensile strain more than 50 times that of ordinary concrete. As a participant in drafting the industry standard "General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components," Qinglong has established a strict fiber dispersion testing process to ensure uniform fiber distribution in every cubic meter of concrete.

Chemical Admixtures: The "Catalyst" of Performance Optimization

High-range water reducers are the core guarantee for UHPC to achieve a low water-binder ratio (usually ≤0.25). Qinglong uses polycarboxylate-based high-performance water reducers, enabling the concrete to maintain good workability even with low water content. In addition, the precise combination of admixtures such as defoamers and expansion agents effectively resolves air bubble issues caused by UHPC's high density and the risk of shrinkage cracking. This technical expertise is the key support behind Qinglong's ability to complete complex GRC/UHPC projects such as the Dongguan Women and Children's Activity Center.

From the scientific proportioning of raw materials to full-chain quality control, UHPC's outstanding performance stems from the relentless pursuit of every detail. Built on 28 years of industry experience, Qinglong Group deeply integrates material properties with engineering practice. It has not only participated in formulating multiple national and industry standards, but also continuously drives innovative applications of UHPC in real estate, municipal engineering, overseas projects, and other fields through 58 patented technologies. Choosing UHPC is not just choosing a material, but choosing a building solution that combines strength, aesthetics, and durability—a vivid practice of Qinglong's mission to "create aesthetically beautiful architecture."