Key Points and Technical Specifications to Note in UHPC Construction: An Analysis

In the field of architectural decoration materials, Ultra-High Performance Concrete (UHPC) is becoming the preferred material for landmark buildings and high-end projects thanks to its outstanding mechanical properties and design expressiveness. However, the complexity of the UHPC construction process places extremely high demands on technical specifications and detail control. As an industry-leading enterprise with 28 years of full-chain experience in UHPC/GRC/GRG/GRP, Qinglong Group combines the practice of hundreds of key projects to provide an in-depth analysis of the key points and technical specifications of UHPC construction, offering professional guidance for designers and project owners.

I. Material Properties and Construction Suitability Control

The construction quality of UHPC materials depends first on a precise grasp of their properties. The material features ultra-high strength (compressive strength up to 150-200MPa), a low water-binder ratio (typically ≤0.2), and excellent durability, but also exhibits flow sensitivity and significant early shrinkage. Before construction, strict incoming material inspection is required, focusing on fiber dispersion uniformity, initial flow (ideally controlled at 250-300mm), and setting time (initial setting ≥4 hours) to ensure that material performance complies with the industry standard "General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components". Qinglong Group's Nanning production base is equipped with a professional testing laboratory, enabling full-process quality monitoring from raw materials to finished products and providing a reliable material guarantee for construction.

II. Formwork Engineering and Pouring Process Specifications

The formwork system is the core guarantee of UHPC forming quality. Since UHPC undergoes considerable volume shrinkage during hardening, the formwork must have sufficient rigidity (a steel section frame plus 15mm thick film-faced bamboo plywood is recommended), with joint gaps controlled within 0.5mm to prevent slurry leakage. Before pouring, a simulated pouring test should be conducted to determine the optimal vibration method — for components with complex shapes, high-frequency vibrators (frequency ≥10000 times/minute) combined with manual assistance are recommended to ensure that air bubbles are fully released. In the Nanjing East Road Century Plaza renovation project, Qinglong used BIM technology to rehearse the pouring process, successfully achieving precise forming of light-transmitting UHPC components, with surface flatness deviation controlled within 2mm/2m.

III. Curing Process and Strength Development Control

Scientific curing is a key step in ensuring that UHPC performance meets standards. Immediately after pouring, the surface should be covered to retain moisture; after initial setting, steam curing should be carried out (temperature gradient ≤20℃/h, maximum curing temperature ≤80℃) for no less than 48 hours. For exposed decorative surfaces, surface treatment should be performed after curing; a dedicated sealant can be applied to improve impermeability and weather resistance. In the Dongguan Women and Children's Activity Center project, Qinglong innovatively adopted an "intelligent curing system", using sensors to monitor the internal temperature of components in real time, ensuring a balance between strength development and volume stability. The project won the Silver Award at the first GRC Construction Engineering Innovation Awards.

IV. Installation Nodes and Structural Safety Assurance

The installation of UHPC components must fully consider thermal deformation and load transfer. Stainless steel connectors should be used for the anchoring system; the spacing of embedded bolts should be determined through structural calculation based on component weight, and the pull-out resistance of a single bolt should be ≥5kN. For long-span components (length >6m), sliding supports should be provided to release thermal stress. As a participating editing unit of the "Technical Standard for Building Applications of Glass Fiber Reinforced Cement (GRC)", Qinglong has developed a "flexible connection node" technology that has been successfully applied in many landmark projects in China, effectively solving the problem of cracking common to traditional rigid connections.

UHPC construction is a comprehensive embodiment of material properties, engineering technology, and management experience. With 28 years of full-chain service experience and integrated solutions from detailed design to after-sales maintenance, Qinglong Group has helped more than a thousand major projects at home and abroad achieve quality delivery. In the future, as UHPC application scenarios continue to expand, standardized construction and technological innovation will become the core drivers of industry development, bringing more possibilities to the field of architectural decoration.