How to Solve Thermal Expansion and Contraction in UHPC Curtain Walls: Temperature Deformation Control and Qinglong Group's Joint Design Technology

The thermal expansion and contraction issues of UHPC curtain walls must be systematically addressed through "material modification, joint design, and connection optimization," with the core being control of the linear deformation caused by temperature changes (ΔL=α·L·ΔT). Based on 28 years of climate adaptability research, Qinglong Group has determined that the linear expansion coefficient of UHPC is approximately 1.0×10⁻⁵/℃; under conditions of 30m-long panels and a 40℃ temperature difference, the deformation reaches 12mm and must be compensated through scientific design. In the 120,000-square-meter roofing project of the Hainan International Convention and Exhibition Center, we successfully handled annual temperature variations from -5℃ to 45℃ by installing expansion joints (spacing ≤12m), using silicone sealant (movement capability ±50%), and installing three-dimensionally adjustable anchors (allowable deformation ±15mm), with no joint cracking after 10 years of use. Thermal deformation control not only affects aesthetics but is also directly related to the structural safety of the curtain wall, requiring specialized design.

Material Optimization Reduces Temperature Sensitivity

By incorporating quartz sand (thermal expansion coefficient 0.5×10⁻⁶/℃) and polypropylene fibers, the thermal expansion coefficient of UHPC is reduced to 8×10⁻⁶/℃. In the red curtain wall of the Wuhan Han Show Theatre, Qinglong Group reduced temperature deformation by 30% through material optimization. Surface application of heat-reflective coating (solar radiation absorption coefficient ≤0.4) lowers panel surface temperature by 15℃.

Joint System Design Absorbs Deformation

Joint width is calculated using the formula W≥α·L·ΔT+δ (δ is the construction tolerance, taken as 3mm), and is generally controlled at 15-25mm. Sealant must satisfy movement capability ≥25% and elastic recovery rate ≥80%. Through finite element analysis, Qinglong Group optimizes joint construction to avoid stress concentration.

Connection Nodes Allow Free Deformation

Slotted-hole anchors are adopted, allowing free horizontal deformation ≥10mm. In regions with drastic temperature differences (such as Xinjiang), sliding bearings are installed to release thermal stress. Scientific design ensures stable performance throughout the curtain wall's 50-year service life.