What to Pay Attention to in UHPC Construction: Key Technical Points and Quality Control Measures Explained

Amid the wave of building material innovation, UHPC (Ultra-High Performance Concrete) is becoming a new favorite in high-end construction with its outstanding mechanical properties and design expressiveness. However, the complexity and technical barriers of its construction process often present numerous challenges for project parties pursuing ultimate quality. As an industry leader with 28 years of deep expertise in UHPC/GRC/GRG/GRP materials, Qinglong Group will draw on its full-chain practical experience to provide an in-depth analysis of the key technical points and quality control measures in UHPC construction—from material properties and process control to quality assurance—offering professional solutions for designers and owners.

I. UHPC Material Properties and Pre-Construction Preparation: Scientific Control Lays the Foundation for Quality

As a fiber-reinforced composite material, UHPC features a low water-binder ratio, high flowability, and rapid early strength development—characteristics that place stringent demands on the construction environment and preliminary preparation. In the standardized processes at its Nanning production base, Qinglong Group consistently emphasizes three core pre-construction preparations: First, the UHPC mix proportion must be precisely adjusted according to project design requirements, with workability, mechanical properties, and durability verified through laboratory trial mixes to ensure the material complies with the industry standard "General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)"; Second, construction molds must be finely treated, using high-precision steel molds or custom FRP molds to ensure a surface flatness deviation of ≤2mm, with a dedicated release agent applied to prevent sticking; Finally, a material entry acceptance mechanism must be established, with each batch of UHPC requiring a factory certificate of conformity, mechanical property test report, and fiber dispersion inspection records to eliminate quality risks at the source.

II. UHPC Casting and Molding Processes: Detail Control Determines Structural Precision

The casting stage is the core control point of UHPC construction quality. Based on thousands of project practices, Qinglong Group has summarized the "Three Highs" construction principle: high flowability assurance, high compactness molding, and high-precision curing. During casting, mechanical vibration combined with vacuum assistance must be used to ensure the concrete fully fills the mold corners, avoiding air bubbles and honeycomb defects; for complex-shaped components (such as double-curved curtain wall panels and openwork landscape features), the casting path is rehearsed through BIM technology, with layered casting on vibration tables, controlling each layer thickness to no more than 300mm. It is worth noting that the initial setting time of UHPC is typically only 4-6 hours, so the casting rhythm must be strictly controlled to prevent cold joints caused by excessive intervals. After molding, a combination of steam curing and natural curing is adopted, with formwork removal only after strength reaches 80% of the design value, effectively preventing early cracking.

III. UHPC Installation and Joint Treatment: Full-Process Management Ensures Project Safety

As a national high-tech enterprise integrating detailed design, manufacturing, and construction installation, Qinglong Group places particular emphasis on the installation precision and structural safety of UHPC components. Before installation, the base structure is re-measured using 3D laser scanning technology, generating point cloud data for comparison with the BIM model to ensure an installation datum deviation of ≤5mm; customized metal connectors are used, whose load-bearing capacity must be verified through pull-out tests, with a single anchor bolt tensile strength of no less than 15kN. For joint treatment—a key difficulty—Qinglong's R&D team has innovatively adopted a "flexible sealing + rigid support" composite system, using low-modulus silicone sealant as the joint filler, combined with UHPC-specific repair mortar for leveling, which meets both deformation compensation requirements and waterproofing performance. In addition, RFID chips are embedded in all installation nodes to achieve full lifecycle quality traceability—a technology successfully applied in benchmark projects such as the Nanjing East Road Century Plaza renovation project.

IV. Quality Control and Acceptance Standards: Full-Chain System Builds a Solid Quality Defense

Quality control of UHPC construction must run through the full chain of "design-production-construction-acceptance." Relying on the technical strengths of its provincial R&D center and engineering technology center, Qinglong Group has established a comprehensive quality management system: during the production stage, automated production lines achieve mix proportion accuracy of ±1% and mixing time deviation of ≤10 seconds; during construction, a "three-inspection system" is implemented for each process, with key monitoring of concrete slump (controlled at 250-280mm), curing temperature (maintained at 20-25℃), and component verticality; the acceptance stage strictly follows the "Ultra-High Performance Concrete (UHPC) Exterior Wall Panels" standard, conducting 100% inspection of surface flatness, compressive strength (≥150MPa), impermeability grade (≥P12), and other indicators. In line with Qinglong's corporate motto of "meticulous workmanship and the pursuit of excellence," every detail from material R&D to project delivery is dedicated to creating safe, durable, and aesthetically valuable architectural works for clients.

From the irregular curtain walls of grand theaters to artistic components in municipal landscapes, UHPC applications are reshaping the formal boundaries of architecture. As a vice-chairman unit of the China GRC Association and a member of the International GRC Association, Qinglong Group will continue to drive industry development through technological innovation, leveraging its full-chain service capabilities to provide solid support for designers in realizing their creative visions and to build premium projects for owners that stand the test of time. On the path of exploring UHPC technology, rigorous construction control and a scientific quality system remain the core code for achieving architectural excellence.