Key Steps and Process Essentials in the Factory Prefabrication Stage of UHPC Curtain Wall Panel Production

Driven by the dual forces of contemporary architectural aesthetics and engineering technology, UHPC curtain wall panels, with their ultra-high strength, excellent durability, and outstanding formability, are becoming the material of choice for landmark building façades. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group deeply understands the decisive role of the factory precasting stage in the final quality of curtain walls. This article systematically analyzes the key process nodes in the precast production of UHPC curtain wall panels, revealing how refined control achieves the perfect transformation from design drawings to architectural art.

I. Material Proportioning and Mixing Process: The Source Guarantee of UHPC Performance

The outstanding performance of UHPC curtain wall panels begins with scientifically precise material formulation. Qinglong Group adopts a proprietary formulation system developed in-house, mixing ultra-fine silica fume, quartz sand, and high-strength steel fibers in golden proportions, combined with a specially formulated high-efficiency water reducer to achieve a low water-binder ratio. In the mixing stage, a twin-shaft compulsory mixer performs a three-stage mixing process—3 minutes of dry mixing ensures uniform material dispersion, 5 minutes of wet mixing promotes the hydration reaction, and finally steel fibers are added and mixed for 2 minutes to achieve uniform three-dimensional distribution. Throughout this process, the mixing temperature must be strictly controlled at 20-25°C to ensure the concrete achieves an initial flow of over 250mm, laying the foundation for subsequent molding. Notably, to meet the needs of projects in different climate zones, Qinglong also dynamically adjusts formulation parameters—for example, in cold regions, the proportion of early-strength components is appropriately increased to guarantee strength development in low-temperature environments.

II. Mold Design and Forming Process: Precisely Replicating Architectural Aesthetics

As customized decorative components, the forming molds of UHPC curtain wall panels directly determine product precision and surface texture. Qinglong adopts a digital mold design solution combining 3D scanning and BIM technology, using Rhino/Grasshopper parametric modeling to achieve precise transformation of complex double-curved surfaces and openwork textures. Aerospace-grade aluminum alloy or epoxy resin composites are selected as mold base materials, ensuring forming errors within 1.5mm. In the pouring stage, a vacuum-assisted casting process combined with high-frequency vibration is employed, allowing the concrete to fully fill the mold cavity under a negative pressure of 0.08MPa, effectively eliminating air bubbles and voids. For artistically complex components, Qinglong innovatively applies variable-angle inclined pouring technology, dynamically adjusting the mold angle between 30 and 60 degrees to solve the compaction challenges in densely reinforced areas during traditional pouring. The key control point at this stage lies in matching the pouring speed with the vibration frequency. Through its parameter database built on 28 years of process accumulation, Qinglong can achieve the optimal process combination for different component types.

III. Curing Regime and Quality Testing: Ensuring Long-Term Performance Stability

A scientific curing regime is the core guarantee of UHPC strength and durability. Qinglong has established a three-stage curing system of "steam curing + natural curing + sealed curing": immediately after pouring, 40°C steam curing for 24 hours promotes early strength development; the panels are then transferred to 20°C constant temperature and humidity curing for 7 days to ensure the hydration reaction is fully completed; finally, surface sealing treatment creates a sustained curing environment. This curing regime enables UHPC curtain wall panels to stably achieve a 28-day compressive strength of over 150MPa and an elastic modulus exceeding 45GPa. In the quality testing stage, in addition to conventional mechanical property tests, Qinglong innovatively introduces ultrasonic flaw detection and chloride ion penetration coefficient testing to assess the internal defects and durability of every curtain wall panel. Especially for large-scale projects, RFID chip embedding technology is adopted to establish a full life-cycle traceability system from raw materials to finished products, providing data support for later operation and maintenance.

From the micro-regulation of materials science to the macro-control of engineering technology, the factory precasting of UHPC curtain wall panels is a systematic project of multidisciplinary collaboration. Drawing on 28 years of technical expertise in the UHPC/GRC/GRG/GRP fields, Qinglong Group carries its quality philosophy of "meticulousness and the relentless pursuit of excellence" through every step of precast production. As a National High-Tech Enterprise and a participant in the formulation of industry standards, Qinglong not only provides architectural designers with the material vehicle to realize their creativity, but also, through its full-chain service capability, allows ultra-high performance concrete—this "material of the future"—to shine with unique value in contemporary architecture. With the deepening application of digital construction technology, the factory precasting process of UHPC curtain wall panels will continue to evolve, offering unlimited possibilities for the innovative expression of building façades.