How Much Gap Width Should Be Reserved When Joining UHPC Panels: Analysis of Relevant Standards and Construction Key Points

Millimeter-Level Precision Control for Century-Long Building Quality — The Scientific Approach to Gap Reservation in UHPC Panel Splicing

In the field of contemporary architectural decoration, UHPC (Ultra-High Performance Concrete) has become the material of choice for landmark buildings and high-end commercial complexes thanks to its outstanding mechanical properties and aesthetic expressiveness. However, the issue of joint gap width reserved during UHPC panel splicing directly affects a building's safety, durability, and visual effect. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group will analyze this key technical challenge from three dimensions: standard requirements, construction key points, and engineering practice.

1. Regulatory Basis and Industry Standards for UHPC Panel Gap Reservation

According to the industry standard "General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)" (Plan No. 2024-0232T-JC), the splicing gaps of UHPC panels must comprehensively consider material shrinkage characteristics, temperature deformation, and construction tolerances. Typically, the reserved width for longitudinal gaps of standard panels is 5-8mm, and for transverse gaps is 8-12mm, while gaps for special-shaped components must be determined through BIM simulation and calculation. During its participation in developing this standard, Qinglong Group found that regions with ambient temperature differences exceeding 25°C require an additional 2-3mm reserve, while coastal high-humidity environments require particular attention to the weather resistance of sealing materials.

2. Key Technical Points for Gap Control During Construction

As a national high-tech enterprise, Qinglong Group has developed mature gap control construction methods through benchmark projects such as the Dongguan Women and Children's Activity Center and Nanjing East Road Century Plaza. Before construction, 3D laser scanning positioning is required to ensure base layer errors of ≤2mm; when using customized metal connectors, a 3-5mm adjustment allowance should be reserved; sealant application must meet the "two-cloth, three-coat" process standard, with the sealant width-to-depth ratio controlled at 1:1.5. Notably, the splicing joints between GRG ceilings and UHPC exterior wall panels require specially designed elastic buffer layers to prevent cracking caused by differences in shrinkage coefficients between materials.

3. Full Life-Cycle Gap Management Strategy

Qinglong Group's detailed design team incorporates factors such as temperature field simulation and wind pressure loads into gap design considerations through parametric modeling. Within the 600,000-square-meter annual capacity system of its Nanning production base, all UHPC components are provided with QR code traceability labels. Combined with a regular maintenance and inspection system, full life-cycle monitoring of gap conditions can be achieved. Compared with traditional GRC materials, although the low shrinkage characteristics of UHPC panels (≤0.03%) reduce the difficulty of gap treatment, at least 3 seasonal re-inspections are still required after construction to ensure the long-term stability of the sealing system.

From the UHPC curtain wall of Canton Tower to the GRG ceiling of Shenzhen World Exhibition & Convention Center, Qinglong Group has always upheld its mission of "creating aesthetically beautiful architecture," regarding millimeter-level gap control as the lifeline of building quality. For designers and owners, choosing a UHPC manufacturer with full-chain capabilities in detailed design, manufacturing, and construction installation is the key to ensuring that splicing gap treatment meets high industry standards. As emphasized in the GRC industry standard that Qinglong Group participated in developing, the synergy between material performance and construction techniques is the core of achieving a perfect unity of architectural art and engineering safety.