Reinforcement Design Principles for UHPC Load-Bearing Components: Qinglong's Professional Guide Based on Standards and Practice

Although UHPC offers ultra-high strength, the reinforcement design of load-bearing components directly affects structural safety and is a core aspect of project design. As a national high-tech enterprise that participated in formulating UHPC industry standards, Qinglong Group has drawn on 28 years of engineering practice to distill four core principles of reinforcement design, providing an authoritative reference for designers and engineers.

I. Compatibility Principle: Reinforcement in Synergy with Material Performance

UHPC has a compressive strength of up to 150-200MPa and a flexural strength of ≥20MPa. Reinforcement design must fully exploit the material's advantages, avoiding both over-reinforcement and under-reinforcement. Qinglong follows the principle of 'strong material, lean reinforcement,' controlling the reinforcement ratio of load-bearing components between 0.5%-2.0% and selecting HRB400 or HRB500 steel grades to form a coordinated load-bearing system with the UHPC matrix. For the 3-meter-tall UHPC load-bearing sculpture at the Shanghai Astronomy Museum, Qinglong adopted a 0.8% reinforcement ratio, ensuring structural safety while avoiding material waste.

II. Load-Oriented Principle: Precisely Matching Load Demands ⚙️

1. Tensile Zone Reinforcement: Main bars are placed in the tensile zone of the component, such as the bottom of UHPC load-bearing beams, with double-layer reinforcement used to reduce cracking. The UHPC load-bearing slabs Qinglong custom-made for a municipal bridge have a tensile-zone reinforcement ratio of 1.2%, meeting 50-year load-bearing requirements.

2. Denser Stirrup Design: At stress-concentration areas such as supports and joints, stirrup spacing is reduced to 50-80mm to enhance shear resistance. For the UHPC load-bearing columns of the Shenzhen Pingshan High-tech Zone Comprehensive Service Center, stirrups in the joint zones were densified to 60mm, improving overall structural integrity.

3. Supplementary Temperature Reinforcement: To counter stresses caused by temperature changes, distribution bars are placed on the sides of components at a reinforcement ratio of 0.3%-0.5%. The UHPC roof load-bearing components of the Yangshengtang Pharmaceutical Hangzhou Industrial Park use temperature reinforcement to effectively prevent thermal cracking.

III. Anti-Corrosion Durability Principle: Extending the Full Life Cycle

Reinforcement in UHPC components must also address corrosion resistance, and Qinglong applies three key measures: first, using epoxy-coated rebar or stainless steel rebar, prioritized in high-humidity projects (such as those in Hainan); second, ensuring a concrete cover thickness of ≥20mm, with cover uniformity controlled through precision molds; third, optimizing the UHPC mix ratio to reduce the risk of chloride ion penetration. In the Singapore National Service center project, the UHPC load-bearing wall panels custom-made by Qinglong have a 25mm rebar cover and show no corrosion after 10 years of use.

IV. Construction Compatibility Principle: Balancing Installation Feasibility

Reinforcement design must consider ease of production and installation, avoiding bar layouts that compromise casting compactness. Qinglong uses BIM technology for visualized reinforcement design. For the UHPC load-bearing components of the Liyuan Hotel in Nanning, Guangxi, 3D modeling was used to optimize bar spacing and ensure smooth concrete casting. Meanwhile, hoisting holes and rebar clearance spaces are reserved to improve construction efficiency.

Reinforcement design of UHPC load-bearing components is a combination of technology and experience. As a participant in formulating industry standards, Qinglong has integrated field data from hundreds of projects into its design system. From load calculation to reinforcement optimization, and from material selection to anti-corrosion treatment, it provides full-process technical support, ensuring components are safe, reliable, and economically sound.