How Wide Should the Gap Be When Splicing UHPC Panels: Analysis of Reasonable Standards and Construction Key Points

Millimeter-Level Precision Control for Perfect UHPC Panel Joining — A Practical Guide from Qinglong's 28 Years of Technical Expertise

In the field of contemporary architectural decoration, UHPC (Ultra-High Performance Concrete) has become the ideal choice for high-end projects such as grand theaters, commercial complexes, and landmark buildings, thanks to its ultra-high strength, excellent durability, and outstanding formability. As a pioneer in China's UHPC/GRC/GRG/GRP materials sector, Qinglong Group (Guangdong Qinglong Construction Engineering Co., Ltd.) draws on 28 years of full-chain experience and deeply understands the decisive impact of UHPC panel jointing techniques on engineering quality. This article systematically analyzes reasonable gap-width reservation schemes for UHPC panel joints from three dimensions—standard requirements, influencing factors, and construction key points—providing a professional reference for designers and owners.

### I. Standards Baseline and Industry Consensus for UHPC Panel Joint Gaps

According to industry standards such as the General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components (Plan No. 2024-0232T-JC), together with the technical requirements of Ultra-High Performance Concrete (UHPC) Exterior Wall Panels (T/CBMF171-2022), which Qinglong helped develop, the reservation of UHPC panel joint gaps must meet three core needs: **temperature deformation, dry-wet shrinkage, and construction tolerances**. Under normal conditions, the width of flat-surface joint gaps is recommended to be controlled at **5-10mm**, while curved or specially shaped components may be appropriately widened to 8-15mm depending on the radius of curvature. This parameter takes into account both the low shrinkage rate of the UHPC material itself (typically ≤0.03%) and the adjustment allowance during on-site installation, ensuring structural stability even under extreme conditions with temperature variations of ±50℃.

### II. Analysis of Four Key Factors Affecting Gap Width

1. **Material Properties and Component Dimensions**: When UHPC panels exceed 6 meters in length, it is recommended to increase the gap width by 1-2mm for every additional 2 meters to offset linear expansion effects. During prefabrication at Qinglong's production base, hydration heat is precisely controlled through steam curing, reducing early-stage shrinkage to below 0.025% and providing more stable baseline data for gap reservation.

2. **Installation Environment and Climate Conditions**: In northern regions with large temperature differences or high-humidity environments (such as coastal projects), the "temperature gradient method" should be used to calculate gaps—for example, reserving 8-10mm for winter construction, which can be reduced to 5-7mm for summer construction. Qinglong's overseas projects (such as a commercial complex in Saudi Arabia) use BIM technology to simulate annual temperature fields, achieving dynamic gap optimization.

3. **Structural Design and Waterproofing Requirements**: When joints must fulfill waterproofing functions, the width should be adjusted according to sealant performance. Qinglong recommends the **"backing rod + two-component silicone sealant"** system, with the gap width-to-depth ratio controlled at 1:1.5 to ensure watertightness and elastic cushioning.

4. **Construction Precision and Modular Installation**: Qinglong's independently developed "3D laser positioning + prefabricated connectors" technology keeps installation errors within ±2mm, reducing redundant gap reservations. In the Nanjing Road Century Plaza renovation project, this technique reduced the standard deviation of transmissive UHPC panel joint gaps to 1.2mm, achieving a "mirror-level" visual effect.

### III. Qinglong's Full-Chain Solution: Key Points of Gap Control from Design to Maintenance

As a national high-tech enterprise and a participant in standards development, Qinglong has established a full-process quality control system covering **detailed design, manufacturing, construction and installation, and after-sales maintenance**:

• **Design Phase**: Rhino+Grasshopper parametric design is used to simulate gap deformation under different loads and output customized node detail drawings;

• **Production Stage**: Automated production lines ensure component dimensional tolerances of ≤±0.5mm/m, with 100% 3D scanning inspection before delivery;

• **Construction Process**: A professional installation team uses Qinglong's patented adjustable supports to achieve millimeter-level fine adjustment;

• **After-Sales Maintenance**: Digital records are established to regularly monitor gap changes, with sealant replacement and structural inspection services provided within the 10-year warranty period.

### Conclusion: Forging Detail Quality Through Professional Expertise

The gap reservation for UHPC panel joints may seem trivial, but it is in fact a comprehensive embodiment of materials science, structural mechanics, and construction technology. For 28 years, Qinglong Group has adhered to the philosophy of "meticulousness and excellence," transforming millimeter-level detail control into the perfect presentation of architectural art through 58 patented technologies and full-chain service capabilities. Whether for domestic landmark projects or overseas engineering, Qinglong remains committed to its mission of "creating beautiful architecture," providing designers and owners with integrated solutions from concept to completion, and supporting the high-quality application of UHPC materials in architectural decoration.