Key Points and Practical Discussion on Connection Joint Design Between UHPC Curtain Wall Panels and Steel Frame Keels

In modern building curtain wall technology systems, the design of connection joints between UHPC curtain wall panels and steel frame keels is a core factor determining building safety and aesthetic expressiveness. As an industry participant with 28 years of experience in detailed design and engineering practice of UHPC/GRC/GRG/GRP materials, Qinglong Group deeply understands the "skeletal" role of connection joints in curtain wall systems—they must not only bear the material's self-weight and external loads, but also coordinate the complex relationship between UHPC material properties and the building's dynamic deformation. This article systematically analyzes the key design points of connection joints between UHPC curtain wall panels and steel frame keels from three dimensions: structural safety, construction technology, and engineering practice.

I. Structural Safety Design Principles for Connection Joints between UHPC Curtain Wall Panels and Steel Frame Keels

Ultra-high performance concrete (UHPC), with its compressive strength exceeding 150MPa and excellent durability, has become an ideal material for curtain wall systems, but connection joint design must focus on resolving three major contradictions: compatibility between material rigidity and building deformation, uniformity of concentrated load transfer, and weather resistance during long-term service. In the Nanjing East Road Century Plaza renovation project, Qinglong's technical team innovatively adopted a composite joint scheme of "flexible hinging + rigid limiting," controlling joint displacement within 0.5mm through an integrated casting process combining 304 stainless steel embedded parts with the UHPC panel body, while meeting the seismic requirements of the translucent concrete curtain wall. Practice shows that rational joint design should follow the "strong joint, weak member" principle, optimizing stress distribution through finite element simulation to ensure that joints remain in an elastic working state under wind loads and thermal deformation.

II. Material Matching and Construction Technology Innovation for Connection Joints

The connection quality between UHPC curtain wall panels and steel frame keels depends on the dual guarantees of material compatibility and construction precision. The full-process quality control system established at Qinglong's production base in Nanning, Guangxi, places particular emphasis on the machining precision of joint components—embedded part position deviation is strictly controlled within ±2mm, and stainless steel connectors are CNC-machined to ensure fitting tolerances. In the Dongguan Women and Children's Activity Center project, to meet the composite connection requirements of GRC decorative lines and UHPC curtain wall panels, Qinglong developed a "toothed-slot mechanical interlocking + structural adhesive assistance" connection process, which avoids the durability risks of relying solely on adhesive bonding while enhancing pull-out resistance through mechanical interlocking. It is worth noting that joint anti-corrosion solutions should be selected according to different climate zones: 316 stainless steel is recommended for tropical regions, while cold regions require the addition of elastic gaskets to absorb freeze-thaw deformation.

III. Joint Design Optimization Strategies in Engineering Practice

Complex building forms pose greater challenges to connection joints. The industry standard "General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)", which Qinglong participated in formulating, systematically summarizes joint solutions for three typical scenarios: for the large-span curved curtain walls of commercial complexes, three-dimensional adjustable joints are used to achieve installation error compensation; for the special-shaped components of landmark buildings, joint parametric design is carried out through BIM technology—for example, in a provincial capital grand theater project, every connection joint of the double-curved UHPC curtain wall panels was individually modeled and calculated; and in coastal environment projects, the innovative application of dual anti-corrosion technology combining the sacrificial anode method and silane impregnation has extended joint service life to more than 50 years. These practices have verified the reliability of UHPC curtain wall systems under various complex working conditions, and also demonstrated Qinglong's industry-leading position in joint technology R&D as a national high-tech enterprise.

Although connection joints are a "microscopic" component of the curtain wall system, they directly relate to building safety and the realization of design concepts. Qinglong Group's 28 years of engineering experience show that excellent joint design should be an organic unity of structural logic, material properties, and construction technology. With the widespread application of new building materials such as UHPC in the field of architectural decoration, connection technology will develop toward greater refinement and intelligence—from BIM pre-assembly to digital twin operation and maintenance, from passive load-bearing to active vibration damping, joint systems are becoming a key support point for the industrialization and green transformation of construction. As a full-chain service provider in the field of UHPC/GRC/GRG/GRP materials, Qinglong will continue, with the craftsmanship spirit of "meticulous attention to detail and constant pursuit of excellence," to provide designers and owners with safe, reliable, and creative joint solutions, helping to create more architectural works that combine aesthetic value with technical substance.