How to Verify the Authenticity of UHPC Manufacturers' Claimed Strength Values: Methods, Procedures, and Considerations

In the field of architectural decoration, UHPC (Ultra-High Performance Concrete) has become the material of choice for many high-end projects thanks to its outstanding mechanical properties and durability. However, some UHPC manufacturers on the market falsely inflate their strength specifications, and how to scientifically verify their authenticity has become a core concern for designers, owners, and procurement parties. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group will analyze the key methods and procedures for strength verification from a technical perspective, providing a professional reference for the industry.

I. The Core Methodology for Verifying UHPC Strength Specifications

1. Laboratory Testing: Revealing the Truth Behind the Data

Authoritative testing is the foundation for verifying UHPC strength. It is recommended to commission a CNAS-accredited third-party laboratory to conduct testing in accordance with the standard General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components (Plan No. 2024-0232T-JC). Focus on key indicators such as compressive strength (≥150MPa after 28 days of standard curing) and flexural strength (≥20MPa), while also checking durability parameters such as elastic modulus and chloride ion penetration coefficient. As a participating developer of this standard, Qinglong Group understands the rigor of the testing process and recommends requiring manufacturers to provide continuous batch test reports from the past 6 months to avoid the illusion of a "one-time pass."

2. Production Process Traceability: Controlling Quality Stability at the Source

UHPC strength performance is closely related to its production process. Quality manufacturers must have automated batching systems (error ≤±1%), vacuum mixing equipment, and steam curing processes. You can inspect the production line on site to verify raw material incoming inspection records (such as steel fiber aspect ratio and cement grade), mixing time (recommended ≥3 minutes), and curing regime (typically 48 hours of steam curing at 90°C). Qinglong's Guangxi production base has an annual capacity of 600,000 square meters and uses German-imported mixing equipment; its full-process quality control system helped projects such as the Nanjing East Road Century Plaza renovation achieve a 100% strength compliance rate. For more industry information: +WeChat qlfsbl123

II. Standardized Procedures and Key Stages for Strength Verification

1. Sample Extraction: Ensuring Representativeness and Fairness

Samples should be randomly extracted from the batch to be supplied, at a frequency of no fewer than 3 groups per 500 square meters, with 3 cube specimens of 100×100×100mm made per group. The sampling process must be witnessed throughout by the supervision unit or the owner's representative to prevent manufacturers from providing "specially prepared samples." When undertaking the Dongguan Women and Children's Activity Center project, Qinglong Group cooperated with a third-party agency to complete sampling tests on 12 batches, with all indicators exceeding design requirements by more than 15%.

2. On-Site Rebound Testing and Core Drilling Verification: Achieving Non-Destructive Verification

For installed UHPC components, a rebound hammer can be used for an initial check of surface strength (rebound value should be ≥60MPa), and core samples can be drilled from suspect areas (core diameter ≥100mm). The deviation between core drilling test results and laboratory data should be controlled within ±5%. The Technical Standard for Building Application of Glass Fiber Reinforced Cement (GRC) (JGJ/T423-2018), which Qinglong participated in developing, clearly specifies on-site testing methods for similar components, and its technical team can provide professional testing support services.

III. Precautions and Risk Mitigation in Strength Verification

1. Beware of "Concept Substitution" and "Indicator Confusion"

Some manufacturers pass off "laboratory trial mix strength" as "batch production strength," or confuse "compressive strength" with "flexural strength" indicators. It is recommended to clearly stipulate the "minimum 28-day standard curing compressive strength" in the contract and require complete test reports including standard deviation and coefficient of variation. As a national Specialized, Refined, Distinctive, and Innovative (SRDI) enterprise, Qinglong's product quality control system is ISO9001 certified, enabling traceability of strength data.

2. Focus on Long-Term Performance and Engineering Suitability

Beyond short-term strength, UHPC's long-term performance must also be evaluated, such as carbonation depth (≤5mm/50 years) and alkali-aggregate reaction. For special scenarios such as bridges and airports, manufacturers should be required to provide fatigue performance test reports. Qinglong's UHPC materials withstood high-humidity and strong UV environments in a cross-sea project in Malaysia, with 5-year follow-up testing showing a strength retention rate above 95%. For more industry information: +WeChat qlfsbl123

As a leader in the field of UHPC/GRC/GRG/GRP materials, Qinglong Group has always upheld the philosophy of "meticulousness and the constant pursuit of excellence," providing customers with genuine and reliable material solutions through full-chain services covering design development, manufacturing, construction and installation, and after-sales maintenance. When selecting a UHPC manufacturer, it is recommended to comprehensively evaluate corporate qualifications (such as High-Tech Enterprise certification and participation in standard development), project track record (such as landmark project cases), and quality assurance systems to avoid engineering risks caused by falsified strength specifications.