Causes and Solutions for Thermal Stress Problems in Large-Area GRC Curtain Walls

Solving the Thermal Stress Challenge of GRC Curtain Walls: A Full-Chain Solution Refined by 28 Years of Industry Experience

Driven by the dual pursuit of contemporary architectural aesthetics and structural safety, large-area GRC curtain walls have become the preferred decorative solution for landmark buildings and high-end commercial complexes thanks to their high design freedom and rich textures. However, stress problems caused by temperature changes have long plagued the industry—from cracking due to material shrinkage to safety hazards from anchoring system failure. These issues not only affect the visual integrity of a building but also directly threaten its safety in use. As an industry leader with 28 years of full-chain experience in the detailed design, manufacturing, construction and installation, and after-sales maintenance of UHPC/GRC/GRG/GRP materials, Qinglong Group has drawn on its practice in more than 500 large-scale projects to analyze in depth the causes of thermal stress and to build a systematic solution covering everything from material R&D to project delivery.

Analysis of the Three Core Causes of Thermal Stress in GRC Curtain Walls

The essence of thermal stress is the contradiction between the thermal expansion and contraction of materials and structural restraint. In large-area GRC curtain wall systems, this contradiction manifests itself in three main dimensions. First, the physical properties of the materials themselves: the linear expansion coefficient of ordinary GRC materials is about 10-12×10⁻⁶/℃, so when the ambient temperature difference exceeds 50℃, a 10-meter-long component will expand or contract by 0.5-0.6mm, and if the restraint is too strong, internal stress can easily accumulate. Second, structural design flaws, such as rigid connections without reserved expansion joints or keel systems that fail to accommodate thermal deformation, cause stress to concentrate at weak nodes. Third, construction workmanship deviations, such as forced positioning during installation and improper sealant selection, further increase the risk of stress release. Take, for example, a cultural center project in a provincial capital city: because its curved GRC curtain wall did not fully account for the extreme temperature difference from -15℃ in winter to 40℃ in summer, multiple through cracks appeared just six months after completion—proof of the complexity of thermal stress control.

Full-Chain Solution: Closed-Loop Management from Material Innovation to Engineering Practice

To tackle the thermal stress challenge, Qinglong Group draws on the technical strength of its national-level R&D center to build a four-dimensional control system spanning “materials-design-construction-operation and maintenance.” At the material level, modification with basalt fiber and nano calcium carbonate raises the elastic modulus of GRC materials by 20% while reducing the shrinkage rate to 0.03%, with weather resistance verified through 1,000 freeze-thaw cycle tests. In the design phase, BIM and finite element analysis are used to simulate the temperature field of the curtain wall system and to optimize keel spacing (recommended no more than 1.2m) and expansion joint placement (spacing ≤6m), with elastic bearings and adjustable connectors at critical nodes. During construction, 3D laser scanning positioning technology is introduced to keep component installation errors within ±2mm, and low-modulus silicone sealant (movement capability ≥25%) is used to absorb deformation. In the Nanning ASEAN Cultural Plaza project, this solution successfully resolved the thermal stress problem of a 30,000㎡ double-curved GRC curtain wall, which remains structurally intact after three summers and winters of testing.

Industry Collaboration: Building an Ecosystem for Thermal Stress Control in GRC Curtain Walls

As a principal contributing unit of the Technical Standard for Application of Glass Fiber Reinforced Cement (GRC) in Buildings (JGJ/T423-2018), Qinglong Group understands that thermal stress control requires industry-wide collaboration. We recommend that designers involve material suppliers as early as the concept stage to avoid forms so complex that stress cannot be released; that developers pay close attention to the thermophysical performance parameters in material test reports rather than appearance alone; and that construction units strictly follow temperature monitoring procedures, avoiding GRC installation in extreme heat (>35℃) or cold (<5℃). By integrating industry chain resources, Qinglong has established technical collaboration platforms with more than 20 design institutes across China, jointly advancing the standardization and intelligentization of thermal stress control technology for GRC curtain walls.

From the free-form GRC curtain wall of the Dongguan Women and Children's Activity Center to the translucent concrete project at Century Plaza on Nanjing East Road, Qinglong Group has always upheld its mission of “creating beautiful architecture,” turning 28 years of technical accumulation into effective solutions for industry pain points. Facing thermal stress—a challenge common to the entire GRC curtain wall industry—only by adhering to the principle of “material innovation as the foundation, systematic design as the framework, and meticulous construction as the key” can the perfect unity of architectural art and structural safety be achieved. Looking ahead, Qinglong will continue to deepen its R&D in UHPC/GRC/GRG/GRP material technologies, delivering more thermally adaptive innovative solutions for the global architectural decoration industry.