How Do UHPC Exterior Walls in Severe Cold Regions Resist Freeze-Thaw Damage? Anti-Freeze Technology and Qinglong Group's Cold-Region Engineering Practice

In severe cold regions, frost damage resistance of UHPC exterior walls must be addressed through a systematic approach of "material modification, structural design, and process control," with the core indicator requiring a frost resistance grade ≥F300 (strength loss ≤20% after 300 freeze-thaw cycles). In projects such as the Harbin Grand Theatre in Heilongjiang and Urumqi Airport in Xinjiang, Qinglong Group achieved 10 years of frost-free UHPC performance under annual temperature variations from -40℃ to 60℃ by adding air-entraining agents (air content 4-6%), controlling the water-cement ratio ≤0.33, and installing drainage cavities (thickness ≥20mm). The essence of freeze-thaw damage is the expansion stress of freezing water; systematic design is required to block water infiltration paths.

Mix Proportion Optimization for Frost Resistance

Sulphoaluminate cement (freezing point -15℃) is preferred, with silica fume (20-30%) added to refine pore size. After 300 freeze-thaw tests, Qinglong UHPC retained a dynamic elastic modulus of ≥90%. In the Shenyang project, mix optimization raised frost resistance to F400.

Moisture-Proofing and Drainage in Structural Design

A "rainscreen" structure is adopted, balancing the cavity behind panels with outdoor air pressure. Joints use elastic sealant (movement capability ≥35%), with drain holes at the bottom. In the double-curved panels of the Harbin Grand Theatre, drainage paths were optimized to prevent winter water accumulation.

Seasonal Control in Construction and Maintenance

Winter construction uses heated enclosure curing (temperature ≥5℃). Qinglong Group provides customized solutions for cold-region projects to ensure quality. Systematic protection is the key to UHPC durability in cold regions.