What Are the Raw Materials of UHPC? An Analysis of Qinglong UHPC Raw Material Selection and Quality Control

The raw material composition of UHPC is highly specialized, mainly comprising cementitious materials, aggregates, fibers, admixtures, and water. Precise proportioning of each component is essential to achieve ultra-high strength and excellent durability. As an industry benchmark with 28 years of dedicated experience in the UHPC field, Qinglong Group has established strict raw material selection standards and a quality control system to ensure stable product performance from the source.

I. Core Cementitious Materials: The Foundation of Strength

High-grade cement: P.O 52.5 or higher grade pure white cement is preferred, meeting requirements for high strength, low hydration heat, and good stability. Qinglong uses imported high-grade white cement to ensure UHPC matrix strength meets standards. Active admixtures: mainly including silica fume, ultra-fine mineral powder, and fly ash. Silica fume requires purity ≥92% and specific surface area ≥15000m²/kg; it can fill cement hydration voids and improve density. Qinglong controls the silica fume content in its UHPC at 10%-15% to optimize the matrix microstructure. Composite cementitious system: through coordinated proportioning of cement and admixtures, a balance between strength and workability is achieved. Qinglong's patented composite cementitious formula enables UHPC compressive strength to stably exceed 120MPa, far surpassing the industry average.

II. Key Aggregate Components: The Core of Density Optimization

Ultra-fine quartz sand: high-purity quartz sand with a particle size of 0.1-1.2mm is selected, with SiO₂ content ≥99% and continuous, uniform particle gradation. Qinglong uses three-graded quartz sand with excellent filling effect to enhance UHPC density. Special aggregates: for functional requirements such as stone imitation and wood imitation, natural colored sand, wood chip fibers, and more can be added. In Qinglong's Shanghai New World UHPC wood-imitation translucent panel project, natural wood-grain aggregates were added to achieve realistic texture effects. Aggregate pretreatment: drying (moisture content ≤0.5%), screening, and other treatments are required to prevent impurities and moisture from affecting performance. Qinglong's raw material pretreatment pass rate reaches 100%.

III. Reinforcing Fiber Materials: The Key to Enhanced Mechanical Performance

Stainless steel fibers: straight stainless steel fibers with a diameter of 0.15-0.25mm and a length of 12-18mm are the mainstream choice, with tensile strength ≥2000MPa and a dosage of 2.0%-3.0%. Qinglong uses imported stainless steel fibers with good dispersibility, significantly improving UHPC flexural and impact resistance. Alkali-resistant glass fibers: alkali-resistant glass fibers can be selected for certain applications, requiring alkali resistance retention ≥85%. For decorative UHPC products, Qinglong optimizes the glass fiber blending scheme to balance strength and design flexibility. Fiber dispersion technology: dedicated dispersants and mixing processes prevent fiber agglomeration. Qinglong adopts a step-by-step mixing method, achieving fiber dispersion uniformity of over 98%.

IV. Functional Admixtures and Water: The Core of Workability Adjustment

High-range water reducers: polycarboxylate-based high-performance water reducers are selected with a water reduction rate ≥35%, which can reduce the water-binder ratio to 0.18-0.22. Qinglong customizes water reducer formulas to fit its own cementitious system and improve mix fluidity. Other admixtures: defoamers, retarders, expansion agents, and more are added as needed. Defoamers reduce bubble defects, and retarders suit high-temperature construction. Qinglong precisely controls admixture dosage at 0.5%-2.0%. Mixing water: purified water or standard-compliant tap water is used, with Cl⁻ content ≤50mg/L, to prevent impurities from affecting the hydration reaction. All of Qinglong's production water undergoes purification treatment, with a water quality compliance rate of 100%.

Precise selection and proportioning of UHPC raw materials are the core guarantee of its high performance. Through strict raw material admission standards, precise proportioning, and pretreatment processes, Qinglong Group controls product quality at the source. Choosing a manufacturer with comprehensive raw material control capabilities is a key prerequisite for ensuring UHPC projects meet performance standards.