What Effects Can Surface Acid Pickling of UHPC Panels Achieve and Analysis of Its Functions

**Acid Pickling Treatment of UHPC Panels: Unlocking the Deeper Value of Ultra-High Performance Concrete**

In the field of building materials, ultra-high performance concrete (UHPC) has become the material of choice for high-end projects thanks to its outstanding mechanical properties and durability. However, to fully unleash the potential of UHPC, surface treatment technology is especially critical. Acid pickling, a core process in the deep processing of UHPC panels, not only affects the appearance and texture, but also directly determines the material's long-term stability and functional realization. As an industry leader with 28 years of expertise in UHPC/GRC/GRG/GRP materials, Qinglong Group will analyze how the acid pickling process empowers UHPC panels from three aspects: technical principles, practical results, and engineering value.

### I. Acid Pickling: The “Key Code” to Enhancing UHPC Panel Performance The acid pickling of UHPC panels is not a simple surface cleaning; rather, it achieves dual optimization of both microstructure and macroscopic performance through a controlled reaction between the acidic solution and the concrete surface layer. Its core principle lies in using the acid to dissolve free calcium and impurities on the surface layer, forming uniform honeycomb-like micro-pores, while activating the reactive components within the material to enhance interfacial bonding. This process is vividly referred to in the industry as “secondary activation of the material,” and is particularly suitable for scenarios with stringent requirements for surface texture and durability, such as grand theaters and landmark buildings.

### II. Four Core Effects: A Comprehensive Upgrade from Appearance to Performance **1. Precise Shaping of Surface Texture** Acid pickling effectively removes the laitance and imperfections on the surface of UHPC panels, revealing a fine, delicate textural quality. By adjusting the acid concentration and treatment time, diverse effects ranging from matte frosted to stone-like textures can be achieved, meeting the personalized design needs of projects such as commercial complexes and art museums. In the Century Plaza renovation project on Nanjing East Road, Qinglong Group applied a customized acid pickling process to ensure that the light-transmitting UHPC panels retained the material's translucency while acquiring a warm, stone-like touch. **2. Significantly Enhanced Durability and Stain Resistance** The micro-porous structure formed by acid pickling not only improves the material's breathability, but also forms a dense siliceous protective film on the surface, effectively blocking the penetration of corrosive media such as moisture and chloride ions. Testing shows that the impermeability of acid-pickled UHPC panels improves by more than 40%, and they can withstand over 300 freeze-thaw cycles, making them especially suitable for exterior wall cladding panels and landscape components in coastal areas and high-humidity environments. **3. Optimized Interfacial Bonding** For UHPC components requiring painting, finishing, or composite installation, acid pickling greatly increases surface roughness, improving the adhesion of subsequent coatings or bonding materials by 30%-50%. In a commercial complex project in Guangzhou, Qinglong pre-treated UHPC sunshade panels with acid pickling, successfully solving the problem of coatings peeling off easily in traditional processes and ensuring more than 15 years of decorative durability for the project. **4. Deep Activation of Material Properties** During the acid pickling process, the acid undergoes a secondary reaction with unhydrated cement particles in the UHPC, further generating calcium silicate hydrate gel and increasing the compressive strength of the material's surface layer by 10%-15%. This property gives acid-pickled UHPC panels significant advantages in thin-profile applications, such as ultra-thin decorative moldings, openwork reliefs, and other complex-shaped components, which meet structural safety requirements while achieving lightweight design.

### III. Value in Engineering Practice: Technical Support from Qinglong's Full-Chain Services As a national high-tech enterprise and a participant in developing UHPC industry standards, Qinglong Group incorporates acid pickling into the full life-cycle management of its UHPC products. From process parameter simulation in the detailed design stage, to automated acid pickling production lines in manufacturing, and to surface repair techniques at the installation site, a complete technical system has been formed. For example, in a landmark project in Malaysia, Qinglong applied a combined “acid pickling + sealing” process, enabling the UHPC exterior wall panels to remain free of discoloration and cracking for 5 years in high-temperature, high-humidity conditions, fully verifying the engineering value of acid pickling treatment.

### Conclusion: Process Innovation Drives the Upgrade of Material Value The acid pickling of UHPC panels is both a deep exploration of material performance and a precise expression of architectural aesthetics. Throughout Qinglong Group's 28 years of technical accumulation, process innovations like this have consistently run through the R&D and application of UHPC/GRC/GRG/GRP materials. In the future, as demand for green building and personalized design grows, surface treatment technologies such as acid pickling will become key to unlocking the potential of ultra-high performance materials, bringing more possibilities to the construction industry. Choosing a supplier with full-chain service capabilities is undoubtedly a wise choice for ensuring project quality and long-term value.