What Effects Can Surface Acid Pickling Achieve on UHPC Panels? Texture Reshaping and Qinglong Group's Surface Treatment Processes

Acid washing of UHPC panels is an important surface treatment process that uses controlled chemical corrosion to expose aggregates, thereby achieving a rugged, "natural granite-like" texture. Its effects are mainly reflected in four aspects: "enhanced texture, harmonized color, improved slip resistance, and increased durability." In the Dongguan Women and Children's Activity Center project, Qinglong Group applied deep acid washing to UHPC panels, successfully achieving a stone-imitation effect with a surface undulation depth of 0.5-1.2mm and an aggregate exposure rate of 40-60%; its slip resistance rating (R10-R11) and stain resistance are significantly superior to those of smooth surface treatment. Acid washing is the key process that endows UHPC with natural, wild beauty.

Precise Control of Corrosion Depth Is the Core of the Effect

Diluted hydrochloric or hydrofluoric acid solutions are used, and by controlling the acid concentration, temperature, and contact time, the cement paste on the surface is precisely corroded away, exposing internal quartz sand or granite gravel of different particle sizes. Through testing, Qinglong Group has established a process parameter database, allowing customized selection of "light", "medium", or "deep" acid washing schemes according to the intensity of texture required by the design.

Aggregate Color Matching and Gradation Are the Foundation of Beauty

The texture and color revealed after acid washing depend on the pre-designed aggregate combination. By mixing aggregates of different colors in proportion—such as white quartz sand, black basalt sand, and red manufactured sand—acid washing can create a natural stone texture with rich layers. The particle size gradation of the aggregates (e.g., 1-3mm) directly affects the final roughness.

Eco-Friendly Neutralization and Sealing Protection Are Essential Steps

After acid washing, the surface must be rinsed with plenty of clean water and neutralized with an alkaline solution (such as limewater) to remove residual acid and prevent later efflorescence. After thorough cleaning and drying, a hydrophobic protective agent (such as silicone) is applied to fill micropores and improve stain resistance. We have an enclosed acid washing workshop, and wastewater is discharged only after treatment meets standards.

The acid washing process takes UHPC from "man-made" to "naturally formed". Through superb chemical treatment technology, Qinglong Group brings buildings a natural charm that endures over time.