How to Prevent Cracking of GRC Components During Setting: Key Techniques and Practical Measures

In the field of architectural decoration, GRC components, with their lightweight yet high-strength properties and rich design versatility, are widely used in high-end projects such as grand theaters, commercial complexes, and landmark buildings. However, cracking during the setting process has long been an industry pain point—it not only affects aesthetics and structural safety but may also increase later maintenance costs. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group has drawn on hands-on expertise in detailed design, manufacturing, and installation to develop a systematic crack prevention solution, helping designers and owners achieve high-quality architectural decoration with "zero cracks."

Core Causes of Setting Cracks in GRC Components: The Triple Challenge of Materials, Processes, and Environment

Setting cracks in GRC (Glass Fiber Reinforced Concrete) are not caused by a single factor but result from the combined effects of material mix proportions, production processes, and environmental conditions. In terms of material properties, the hydration reaction of cement-based materials is accompanied by volume shrinkage; if glass fibers bond poorly with the cement matrix, micro-cracks easily form at stress concentration points. During production, uneven mixing leading to unbalanced fiber distribution, premature demolding, or improper curing can directly cause structural defects. Meanwhile, on-site environmental factors such as sudden temperature changes and insufficient humidity intensify shrinkage stresses, ultimately leading to visible cracks. In the course of participating in the development of the Technical Standard for Architectural Application of Glass Fiber Reinforced Cement (GRC) (JGJ/T423-2018), Qinglong Group analyzed data from more than a thousand projects nationwide and found that over 60% of cracking problems can be avoided through early technical intervention.

Key Technologies: Whole-Process Control from Material Optimization to Process Innovation

Solving the challenge of GRC setting cracks requires building a technical defense line at the source. In material formulation, Qinglong adopts "dual admixture technology" to optimize matrix performance: ultrafine mineral powder and fly ash are incorporated to replace part of the cement, reducing the peak hydration heat; at the same time, by precisely controlling glass fiber length (typically 12-25mm) and content (3-5% by volume), the fibers form a three-dimensional randomly oriented support network within the matrix, enhancing crack resistance. During production, BIM technology is introduced to simulate the structural stress of components, with reinforcement added at crack-prone areas such as irregular curved surfaces and cantilevered structures; an automated spray molding process ensures uniform fiber distribution, and film-covered moisture-retention curing is applied immediately after molding, enabling components to reach more than 85% of design strength within 7 days. Taking the Nanjing East Road Century Plaza renovation project as an example, Qinglong applied this technical system to achieve zero-crack delivery of translucent concrete GRC components, winning the Silver Award of the AALBORG WHITE Cup UHPC Construction Engineering Innovation Award.

Practical Measures: Refined Management of Construction, Installation, and Later Maintenance

Even when control at the factory production stage is in place, improper on-site operations can still cause cracking. Qinglong emphasizes coordination across "detailed design-manufacturing-installation": before construction, installation nodes are positioned through 3D scanning, and modular hoisting is adopted to reduce wet work on site. Differentiated installation plans are developed for varying climate conditions—construction is scheduled for early morning or evening in hot seasons, while components are preheated in low-temperature environments to prevent cracking caused by thermal stress. In the after-sales maintenance phase, a "crack early-warning monitoring system" is established; through regular inspections and data feedback, tiny cracks are detected and repaired promptly. With an annual capacity of 600,000 square meters at the Nanning, Guangxi production base, combined with a rapid-response network of offices nationwide, on-site handling within 24 hours is achievable, eliminating crack risks at the earliest stage.

As a National High-Tech Enterprise and a contributor to the formulation of GRC industry standards, Qinglong Group has always upheld the mission of "creating aesthetically beautiful architecture," transforming 28 years of engineering experience into replicable technical solutions. From material R&D to construction implementation, from domestic landmark projects to overseas markets in Southeast Asia, Qinglong applies a meticulous, excellence-pursuing attitude to provide designers with unlimited possibilities for realizing their visions and to safeguard the long-term stability of architectural decoration for owners. Choosing Qinglong GRC means not only choosing a material, but also choosing a crack-resistant solution validated by over a thousand projects, ensuring that every architectural detail stands the test of time.