What Are the UHPC Casting Methods? Comprehensive Analysis and Application Techniques

In the field of contemporary architectural decoration, ultra-high performance concrete (UHPC) has become the material of choice for landmark buildings and high-end projects thanks to its outstanding mechanical properties and design plasticity. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group understands that scientific casting technology is the core element in ensuring UHPC performance. This article systematically analyzes mainstream UHPC casting methods and their key application techniques, providing a professional reference for designers and project owners.

The selection of a UHPC casting process requires comprehensive judgment based on project characteristics, component geometry, and quality requirements. Current mainstream UHPC casting methods fall into four categories: self-compacting casting, spray casting, centrifugal casting, and precast casting, each with its own unique technical points and applicable scenarios.

1. Self-Compacting Casting: An Efficient Choice for Forming UHPC Components
Self-compacting casting takes advantage of the excellent flowability of UHPC material itself, using gravity to achieve automatic filling of the mold without mechanical vibration. This process is suitable for UHPC components with complex geometries and dense reinforcement, such as irregular curtain wall panels and hollow decorative pieces. During construction, the water-binder ratio of the mix (usually ≤0.2) must be strictly controlled, and a stepped casting sequence should be adopted to prevent air bubbles. In the Nanjing East Road Century Plaza renovation project, Qinglong Group successfully achieved precise forming of light-transmitting UHPC components through the self-compacting casting process, with surface flatness deviation controlled within ±2mm, reaching an industry-leading level. For more industry information: WeChat qlfsbl123

2. Spray Casting: A Powerful Tool for Forming Large-Curved UHPC Components
Spray casting uses a high-pressure spray gun to simultaneously spray UHPC mixture and glass fibers onto the mold surface, making it suitable for producing large-span curved components (such as double-curved curtain walls and artistic sculptures). This process significantly improves material density and fiber dispersion uniformity, with flexural strength reaching over 20MPa. In the Dongguan Women and Children's Activity Center project, Qinglong adopted robotic spray technology to complete double-curved GRC-UHPC composite components with a radius of 300mm, improving construction efficiency by 40% compared with traditional processes while achieving excellent surface texture consistency.

3. Centrifugal Casting: Quality Assurance for Tubular UHPC Components
Centrifugal casting generates centrifugal force through high-speed mold rotation, causing the UHPC material to form a uniform, dense structural layer on the inner wall of the tubular mold. It is mainly used for UHPC pressure pipes, cylindrical decorative components, and similar products. The key to construction lies in controlling rotation speed (usually 300-500r/min) and concrete slump (180-220mm) to ensure a component wall thickness deviation of ≤3%. The "General Technical Conditions for Non-Load-Bearing Ultra-High Performance Concrete (UHPC) Components," which Qinglong participated in drafting, provides detailed specifications on quality control standards for the centrifugal process. For more industry information: WeChat qlfsbl123

4. Precast Casting: A Mass Production Solution for Standardized UHPC Components
Precast casting completes UHPC component production in standardized factory molds, accelerating strength development through steam curing (60-80℃ for 24h). It is suitable for standardized products such as curtain wall panels and landscape benches. Qinglong's Guangxi production base is equipped with precast production lines with an annual capacity of 600,000 square meters, using BIM technology for digital mold design, with component dimensional accuracy controlled within ±1mm to meet the rapid delivery needs of large-scale projects.

Regardless of the casting method used, the "Three-Control Principle" summarized by Qinglong Group must be followed: controlling material temperature rise (casting temperature ≤30℃), controlling curing humidity (≥90%), and controlling demolding strength (≥80% of design strength). As a national high-tech enterprise and an industry standard-setting organization, Qinglong will continue to drive the optimization and upgrading of UHPC casting processes through technological innovation, providing solid technical support for its mission of "creating beautiful architecture."