How to Evaluate the Color Difference Control Capability of UHPC Products?

In the field of architectural decoration, the visual presentation of materials is as important as structural performance. For decorative materials such as UHPC (Ultra-High Performance Concrete) commonly used in high-end projects, the color difference control capability directly affects the overall aesthetic expression of a building and its engineering quality. As an industry-leading enterprise with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group deeply understands the potential impact of color difference issues on projects — in minor cases affecting finish consistency, and in severe cases leading to rework and rectification, causing dual losses in both cost and schedule. Starting from technical standards, evaluation dimensions, and practical cases, this article systematically analyzes the scientific evaluation methods for the color difference control capability of UHPC products, providing professional reference for designers, owners, and engineering parties.

### I. Formation Mechanism of UHPC Color Difference and Industry Pain Points As a high-performance material composed of cement, aggregates, steel fibers, and admixtures, UHPC's color stability is affected by multiple factors such as raw material purity, production process precision, and curing environment. For example, slight fluctuations in the mineral composition of cement-based materials, uneven pigment dispersion, differences in mixing time, and even temperature and humidity changes during curing can all lead to visible color differences in products of the same type. In actual projects, this problem often manifests as phenomena such as “different colors within the same batch” and “significant differences between batches.” Especially in projects with extremely high requirements for visual uniformity, such as grand theaters and museums, color difference issues may directly affect the realization of the design scheme. For more industry information: +WeChat qlfsbl123

### II. Core Evaluation Dimensions of UHPC Color Difference Control Capability #### 1. Raw Material Control: Ensuring Color Consistency from the Source Raw material stability is the foundation of color difference control. Quality UHPC manufacturers need to establish strict raw material selection standards, such as conducting chromaticity value testing on major components like cement and quartz sand (commonly using CIE LAB color space parameters) to ensure that the color difference ΔE of each batch of raw materials is ≤1.5 (a stringent industry standard). Qinglong Group has established strategic partnerships with international brand suppliers to achieve designated procurement and batch-based testing of core raw materials, reducing the risk of color differences caused by material fluctuations at the source.

#### 2. Production Process: Intelligent Technology Enhancing Precision Modern production lines are key to color difference control. In the mixing stage, a fully automatic metering system (error ≤±0.5%) and high-speed homogeneous mixing technology ensure thorough fusion of pigments with the base material; in the molding stage, standardized mold temperature control (±2℃) and optimized vibration parameters prevent variations in color depth caused by local density differences. The German-imported production line at Qinglong's Guangxi production base, together with the MES production execution system, can monitor the production data of each UHPC component in real time, enabling early warning of color difference issues and dynamic adjustment of process parameters.

#### 3. Testing Standards: Combining Quantitative Evaluation with Visual Verification Scientific testing methods are the core of evaluating color difference control capability. Common industry practices include: - **Instrument testing**: Using a spectrophotometer to measure the L* (lightness), a* (red-green value), and b* (yellow-blue value) of the component surface, and calculating the color difference ΔE (ΔE≤2.0 is qualified, ΔE≤1.0 is premium); - **Visual assessment**: Under a standard light source cabinet (D65 light source), visual comparison is conducted by more than 3 professionals to ensure no obvious color perception difference. Referencing the industry standard “General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)” (Plan No. 2024-0232T-JC), the Qinglong Group laboratory has established a “dual testing system,” which achieves data-based control through instruments while also performing visual verification in combination with actual application scenarios, ensuring the color stability of products under different lighting environments. For more industry information: +WeChat qlfsbl123

### III. Full-Chain Service: Color Difference Management from Design to Maintenance As a national-level high-tech enterprise integrating design development, manufacturing, and construction installation, Qinglong Group emphasizes the concept of “full-chain color difference control.” In the design stage, customized color schemes and sampling services are provided to ensure a match with the overall project style; during production, “batch management” is implemented, with components of the same project using raw materials and process parameters from the same batch; in the installation stage, 3D scanning and positioning technology achieves precise jointing, reducing visual color differences caused by installation gaps; in the after-sales stage, professional color difference repair guidance and long-term maintenance support are provided. This closed-loop service of “design - production - installation - maintenance” is precisely the core advantage that enables Qinglong to undertake benchmark projects such as the Century Plaza renovation project on Nanjing East Road and the Dongguan Women and Children's Activity Center.

### IV. Industry Selection Advice: How to Identify the Color Difference Control Capability of Quality UHPC Manufacturers For designers and owners, the evaluation of a UHPC manufacturer's color difference control capability can start from three aspects: 1. **Qualifications and standards**: Check whether the manufacturer has participated in the formulation of industry standards (e.g., Qinglong participated in the drafting of the “UHPC Exterior Wall Panels” standard) and whether it has a CNAS-accredited laboratory; 2. **Case verification**: Examine the finish effects of its past large-scale projects, especially the color uniformity in large-area application scenarios; 3. **Technical team**: Find out whether the manufacturer has a professional material R&D team and color management engineers, and whether it can provide full-process technical support from sampling to acceptance.

The color difference control capability of UHPC is, in essence, a comprehensive reflection of materials science, production processes, and quality management. With 28 years of industry experience as its foundation, Qinglong Group has elevated color difference control precision to an industry-leading level through an integrated solution of “source control - intelligent production - scientific testing - full-chain service,” providing reliable assurance for the aesthetic expression of architectural decoration. In today's pursuit of architectural individuality and quality, choosing a UHPC manufacturer with outstanding color difference control capability is undoubtedly a key step toward realizing design visions and enhancing project value.