Effects of Surface Acid Washing on UHPC Panels and Analysis of Its Working Mechanism

Surface treatment technology is a key link in enhancing the performance of UHPC panels, and acid pickling, as an important method among them, is receiving growing attention from UHPC manufacturers. As an industry-leading enterprise with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group has deeply recognized in detailed design and manufacturing that scientific surface treatment not only affects appearance and texture, but also directly influences the material's durability and functional performance. Today, we will analyze the core value of acid pickling treatment for UHPC panel surfaces from two aspects: the mechanism of action and the actual effects.

1. Mechanism of Acid Pickling Treatment for UHPC Panels: Performance Optimization at the Microscopic Level

UHPC (Ultra-High Performance Concrete) has become the preferred material for high-end architectural decoration thanks to its ultra-high strength and excellent durability. However, its initial surface often contains microscopic defects such as cement paste residue and air bubble holes. Acid pickling achieves three core functions through controlled chemical reactions between a weak acidic solution and surface substances: first, the acid solution penetrates and dissolves free calcium compounds on the surface layer, forming a uniform microscopic pore structure and increasing surface roughness; second, it removes oil residues and release agents left by the formwork, eliminating interfacial contamination; finally, it promotes secondary crystallization of hydration products, reinforcing the compactness of the surface structure. This "dissolution-activation-reconstruction" mechanism enables UHPC panels to achieve precise control of surface performance while maintaining the strength of the base material.

2. Four Key Improvements That Acid Pickling Brings to UHPC Panels

In practical engineering applications, acid-pickled UHPC panels demonstrate significant advantages. Verified by Qinglong Group in benchmark projects such as the Nanjing East Road Century Plaza renovation project, the acid pickling process can increase the surface gloss of UHPC panels by more than 30%, effectively presenting the rustic texture of fair-faced concrete or stone-like patterns. More importantly, the treated surface pore structure can improve coating adhesion by 40%, solving the problem of easy peeling in traditional UHPC panel coatings. In terms of durability, the passivated surface layer formed by acid pickling can reduce carbonation depth by 25%; combined with Qinglong's proprietary sealing process, the service life of UHPC components in coastal high-salt-spray environments is extended to more than 50 years. In addition, for irregularly shaped UHPC components, acid pickling can precisely treat subtle flaws on complex curved surfaces, ensuring that surface flatness deviations per square meter are controlled within 2mm.

3. Process Innovation and Quality Control in Industry Applications

As an enterprise that participated in drafting the industry standard "General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)", Qinglong Group has established comprehensive acid pickling process specifications. For different application scenarios, it adopts "customized acid formulations + multi-stage spray processes": in high-end buildings such as grand theaters, a weak organic acid system achieves a matte finish; in municipal landscape components, phosphoric acid-based solutions produce anti-slip surfaces. The entire process uses real-time pH monitoring assisted by ultrasonic cleaning to ensure the acid penetration depth is controlled within the safe range of 0.1-0.3mm. This refined control capability enables Qinglong UHPC products in projects such as the Dongguan Women and Children's Activity Center to meet architects' aesthetic requirements while ensuring structural safety.

From a materials science perspective, the acid pickling treatment of UHPC panels is a typical case of achieving a performance leap through surface modification. Qinglong Group's 28 years of industry experience show that high-quality UHPC products require not only an excellent base material formulation, but also full-process control from detailed design to surface treatment. For developers and designers pursuing architectural quality, choosing a UHPC manufacturer with a complete technical system is the only way to truly realize the application value of this high-performance material. In the future, with the integration of acid pickling processes and digital production, UHPC panels will showcase their charm of "combining rigidity with flexibility" in more landmark buildings.