What Effects Can Surface Acid Pickling of UHPC Panels Achieve? Texture Creation and Qinglong Group's Artistic Treatment Technology

UHPC panel surface acid washing is an artistic finishing process that reveals the aggregate texture through chemical etching, achieving a triple effect of "exposed aggregate, increased roughness, and enhanced color". Surface roughness can be improved from Ra0.8μm to Ra6-12μm, with the friction coefficient increased by more than 50%. In the "Dongguan grass weaving" panel project for the Dongguan Women and Children's Activity Center, Qinglong Group controlled the hydrochloric acid concentration (5-8%), action time (10-30 minutes), and temperature (20-30℃) to uniformly expose quartz aggregates, forming a unique woven texture with a 90% resemblance to real Dongguan grass. Acid washing not only enhances decorative effects but also improves surface slip resistance, making it a perfect combination of function and aesthetics.

Acid washing mechanism and process control. Hydrochloric acid reacts with cement hydration products, dissolving the surface paste and exposing the aggregate. Qinglong Group determined the optimal process parameters through orthogonal tests: at a concentration of 6%, the etching depth is approximately 0.5mm with an aggregate exposure rate of 70%; at 20 minutes, the texture is most uniform. We have established an acid washing workshop where wastewater is neutralized and discharged only after meeting standards, achieving green production.

Texture effects can be precisely designed. Controlling aggregate gradation (e.g., using 2-5mm single-sized aggregate) yields uniform stippled textures, while mixed gradation produces natural random patterns. In an art center project in Shenzhen, we achieved patterned acid washing through formwork masking, creating unique light-and-shadow effects. Acid washing provides designers with a new creative tool.

Post-treatment and performance enhancement. After acid washing, panels must be thoroughly rinsed with water (pH ≥6) and then coated with a fluorocarbon protective layer. The treated surface achieves a slip resistance value of BPN ≥70, reaching anti-slip grade R10. Qinglong Group's acid-washed UHPC panels have been widely used in areas with high slip-resistance requirements such as outdoor platforms and stair treads, balancing safety and aesthetics.