Mandatory Performance Indicators for UHPC Components Before Factory Delivery: Quality Control and Engineering Application Assurance

Factory inspection is a critical step in ensuring that UHPC components meet performance standards and safeguarding project quality. As a national high-tech enterprise with 28 years of full-chain experience in UHPC/GRC/GRG/GRP, Qinglong Group has established a factory inspection system covering 12 core indicators, strictly following the industry standard "General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components," to ensure that every batch of products meets design requirements.

I. Mechanical Performance Indicators: The Core Guarantee of Structural Safety

Mechanical performance is the core property of UHPC components, and compressive strength, flexural strength, and bond strength must be tested before delivery. Qinglong Group stipulates that UHPC components must have a compressive strength ≥150MPa and flexural strength ≥30MPa, tested using standard 150mm×150mm×150mm specimens, with 3 specimens per group averaged and an allowable deviation of ≤±5%. In the Yangshengtang Pharmaceutical Hangzhou Industrial Park project, the sampled UHPC exterior wall panels achieved an average compressive strength of 168MPa, far exceeding standard requirements. Bond strength testing targets the joints between embedded parts and UHPC, requiring ≥3.5MPa; Qinglong uses pull-out tests to ensure secure connections. In addition, for load-bearing components, elastic modulus (≥40GPa) and impact strength (≥12kJ/㎡) must also be tested. For example, the UHPC components of the public art sculptures at the Shanghai Astronomy Museum achieved a 100% pass rate for impact strength.

II. Appearance and Dimensional Deviation Indicators: Basic Requirements for Decorative Effects

UHPC components are mostly used as decorative materials, where appearance and dimensional accuracy directly affect installation results. Appearance quality inspection covers surface defects (cracks, air holes, pitted surfaces), color uniformity, and texture consistency; Qinglong stipulates a surface crack width ≤0.1mm, air hole diameter ≤3mm with no more than 3 holes per square meter, and a color difference ΔE≤2.0. Dimensional deviation inspection uses a laser rangefinder: length and width deviation ≤±3mm, thickness deviation ≤±2mm, flatness ≤2mm/m, and diagonal deviation ≤5mm. For example, the 12㎡ UHPC wood-imitation light-transmitting panels in the Shanghai New World project had all dimensional deviations controlled within allowable limits. For stone-imitation and wood-imitation components, texture fidelity must also be tested, with a requirement of ≥90%; Qinglong verifies this through visual comparison and texture scanning technology.

III. Durability Indicators: Key Guarantee for Long-Term Use

Durability testing ensures that UHPC components remain stable in performance during long-term use, with core indicators including frost resistance, impermeability, and corrosion resistance. Frost resistance is tested by rapid freeze-thaw tests: after 50 freeze-thaw cycles, strength loss must be ≤5% and mass loss ≤1%; the UHPC components in Qinglong's northern projects all passed frost resistance testing. Impermeability requires a penetration height ≤5mm; Qinglong uses the step-by-step pressurization method to ensure that components are leak-free. Corrosion resistance varies by environment: coastal areas require testing for chloride ion penetration resistance (electric flux ≤1000C), and industrial environments require testing for sulfate corrosion resistance. Qinglong conducts specialized tests to ensure that components adapt to different application scenarios.

IV. Qinglong's Inspection System and Standard-Setting Leadership

Qinglong Group has a well-equipped inspection center featuring professional equipment such as universal testing machines, laser rangefinders, and freeze-thaw test chambers, achieving full inspection coverage. The inspection process adopts a "three-level inspection system"—self-inspection by production teams, spot checks by the technical department, and re-inspection by authoritative third-party organizations—to ensure that data is authentic and reliable. As a participant in industry standard-setting, Qinglong has incorporated its own inspection experience into the development of standards such as "Ultra-High Performance Concrete (UHPC) Exterior Wall Panels," promoting the standardization of industry inspection. Backed by strict quality control, Qinglong's UHPC components have passed scientific and technological achievement appraisals in Guangdong Province and the Guangxi Autonomous Region, have won multiple Science and Technology Progress Awards, and have become the designated supplier for well-known enterprises such as Poly and China Overseas, with products exported to overseas markets.

Factory inspection is the last line of defense in UHPC component quality control. Qinglong Group has always upheld the values of "Honesty, Striving, Trust, and Collaboration," performing every test with high standards and strict requirements. Going forward, Qinglong will continue to optimize testing technology and improve testing efficiency and precision, providing customers with higher-quality and more reliable UHPC components and helping to create construction projects that stand the test of time.