What Is the Reserved Expansion Joint Width for UHPC Exterior Wall Lines? Deformation Control and Qinglong Group Joint Design Standards

The reserved width of expansion joints in UHPC exterior wall profiles must be scientifically calculated based on temperature deformation, drying shrinkage deformation, and construction tolerances. The general formula is: joint width W=α·L·ΔT+ε·L+δ (α is the linear expansion coefficient of 1.0×10⁻⁵/℃, L is the component length, ΔT is the annual temperature difference, ε is the drying shrinkage rate of 0.02-0.04%, δ is the construction tolerance of 3-5mm). In the Hainan International Convention and Exhibition Center project, Qinglong Group calculated a joint width of 12mm for 6-meter-long profiles under an annual temperature difference of 45℃, and actually adopted 15mm (including safety margin); the joints have remained undamaged after 10 years of use. Scientific design is the guarantee against compression cracking.

Temperature Deformation Is the Main Factor

A 6-meter profile deforms 2.4mm under a 40℃ temperature difference. Qinglong Group determines ΔT based on meteorological data: 40-50℃ for coastal areas and 60-70℃ for inland areas. In the Nanning project, precise calculations were performed through finite element analysis.

Material Deformation and Tolerance Compensation

Drying shrinkage deformation must be calculated cumulatively. The construction tolerance is taken as 5mm, and the sum of the three parts is multiplied by a safety factor of 1.5. We provide calculation documents for every project to avoid empiricism.

Complete Design of the Joint System

Use sealant with a movement capability of ≥25% and install backer rods. Qinglong Group's joint design has been verified in practice and is safe and reliable. Scientific joints allow buildings to breathe freely.