Mechanism and Impact Analysis of GRC Component Cracking Caused by Steel Corrosion

The durability of a building is not only about aesthetic presentation, but also a core guarantee of structural safety. During the long-term use of GRC (glass fiber reinforced concrete) components, cracking caused by steel reinforcement corrosion is like a hidden “chronic ailment” of buildings—it affects visual appearance and, more importantly, threatens structural stability. As an industry participant with 28 years of deep expertise in UHPC/GRC/GRG/GRP materials, Qinglong Group will reveal the essence of this technical challenge for designers and owners, from mechanism analysis and impact assessment to solutions.

I. How Steel Reinforcement Corrosion Becomes the “Hidden Driver” of GRC Component Cracking

GRC components are made by combining glass fiber with cement-based materials, and the steel reinforcement inside serves as the load-bearing skeleton. Once corrosion sets in, it triggers a chain reaction. During the corrosion process, steel can expand to 2-4 times its original volume, generating enormous tensile stress. When this stress exceeds the tensile strength of the GRC material, irregular cracks appear on the component surface. This “corrosion-expansion cracking” phenomenon is particularly prominent in humid, saline-alkali, or industrially polluted environments. GRC exterior wall cladding panels in coastal areas and decorative components in high-humidity venues, for example, are prone to accelerated steel corrosion caused by chloride ion penetration or carbonation reactions.

II. Analyzing the Multi-Dimensional Impact of Corrosion Cracking on GRC Components

Cracking caused by steel reinforcement corrosion is not an isolated problem; its impact spans the entire life cycle of a component. From a structural perspective, corrosion reduces the steel cross-section and weakens bond strength, lowering the load-bearing capacity of GRC components. In severe cases, it may cause anchorage failure or complete detachment—for instance, the GRC belt course of a commercial complex had to be urgently demolished and rebuilt due to cracking caused by steel corrosion. From an aesthetic perspective, cracks compromise the integrity of the building envelope, and rainwater infiltration further aggravates corrosion, forming a vicious cycle of “cracking—corrosion—more severe cracking” that affects project quality and customer reputation. Moreover, repair costs grow geometrically with the severity of cracking; according to industry research, the repair cost of corrosion problems detected early is only one-fifth of the cost of later replacement.

III. Qinglong GRC Full-Chain Solutions: Blocking Corrosion Risks at the Source

As a national high-tech enterprise, Qinglong Group has drawn on 28 years of full-chain experience to build a “prevention-monitoring-repair” trinity corrosion control system. In material R&D, high-impermeability cement-based formulations and galvanized anti-corrosion steel are adopted, combined with basalt fiber composite reinforcement technology, increasing the chloride ion penetration resistance of GRC components by 40%. During production, precise control of the water-cement ratio and curing processes reduces porosity, lowering the risk of corrosive media intrusion at the source. For existing projects, Qinglong offers BIM-based corrosion monitoring services, using infrared thermal imaging and rebar scanning technology to identify potential hazards in advance. In the field of repair, Qinglong has innovatively applied a UHPC (ultra-high performance concrete) local reinforcement technique, restoring the load-bearing performance of components through non-shrink grouting technology. This has been successfully applied in GRC component maintenance projects for several landmark buildings in China.

IV. Industry Insights: Safeguarding Building Vitality Through Technological Innovation

GRC cracking caused by steel reinforcement corrosion is essentially an interdisciplinary subject spanning materials science, structural engineering, and environmental engineering. As a contributing editor of the “Technical Standard for Building Application of Glass Fiber Reinforced Cement (GRC)”, Qinglong Group has always embedded durability design throughout the entire process of detailed design, manufacturing, and construction installation. For example, in the Dongguan Women and Children's Activity Center project, technologies such as optimizing rebar cover thickness and using epoxy resin-coated rebar enabled the GRC decorative components to achieve a 15-year record free of corrosion cracking. This confirms that only by deeply integrating material innovation with engineering practice can the challenge of building durability be truly solved.

The safety and beauty of buildings require professional protection. With the mission of “creating aesthetically beautiful architecture”, Qinglong Group continues to explore the performance boundaries of UHPC/GRC/GRG/GRP materials, providing designers with solutions that combine aesthetic expressiveness with structural reliability, so that every architectural detail stands the test of time.