Cause Analysis and Solution Strategies for Thermal Stress Problems in Large-Area GRC Curtain Walls

In the development of modern building curtain wall technology, Glass Fiber Reinforced Concrete (GRC) has become an ideal choice for landmark building envelope design thanks to its lightweight, high-strength, and flexible-forming characteristics. However, the stress problems generated by large-area GRC curtain walls under temperature changes have always been a technical challenge that the industry urgently needs to overcome. As an industry leader with 28 years of deep expertise in UHPC/GRC/GRG/GRP materials, Qinglong Group has leveraged its full-chain technical accumulation to build a systematic thermal stress solution, covering material properties, design logic, and construction technology.

I. Analysis of the Underlying Causes of Thermal Stress in GRC Curtain Walls

GRC material is composed of a cement-based composite and a glass fiber reinforcement system, with a thermal expansion coefficient of approximately 10-12×10⁻⁶/℃. Under day-night temperature differences, seasonal transitions, or solar radiation, curtain wall panels produce significant thermal expansion and contraction effects. When such deformation is constrained by the structure or displacement coordination between panels is insufficient, thermal stress concentration occurs, manifesting in three core contradictions: first, the difference in stiffness between the material's own elastic modulus and the base structure leads to uncoordinated deformation; second, the "overall rigidity" formed by large-area continuous installation weakens the capacity for local stress release; third, the aging failure of traditional sealing rubber strips under extreme temperature differences aggravates compression damage between panels. A convention and exhibition center project once failed to fully consider thermal stress, resulting in more than 30 instances of curtain wall panel cracking within 6 months of completion, with direct economic losses exceeding one million yuan.

II. Full-Chain Prevention and Control: Qinglong's Thermal Stress Solution Strategy for GRC Curtain Walls

To address the complex challenge of thermal stress, Qinglong Group has innovatively proposed a trinity solution of "material optimization–structural design–construction control." At the material level, by incorporating nano-scale mineral powder and modified polypropylene fibers, the thermal expansion coefficient of GRC is reduced by 15%, while the material's ultimate tensile value is raised to above 3.5MPa, enhancing crack resistance at the source. During the structural design stage, a parametric BIM model is used to simulate the annual temperature field distribution and dynamically optimize curtain wall joint divisions—for example, in regions above 30° latitude, the horizontal spacing between panels is adjusted from the traditional 10mm to 15-20mm, and slidable aluminum alloy connectors are embedded to achieve ±30mm horizontal displacement compensation.

Refined control of the construction phase is equally critical. Qinglong's original "3D laser positioning + modular installation" process keeps panel installation errors within ±2mm, ensuring uniform distribution of movement joints. In a cultural center project, by setting up an elastic cushioning layer at the back of the GRC curtain wall combined with the flexible connection of silicone structural sealant, the panel deformation caused by thermal stress was successfully controlled to within 0.3mm/m—far below the industry standard limit of 0.5mm/m.

III. Industry Practice: From Technological Innovation to Standard Leadership

As a major contributing unit of the Technical Standard for Application of Glass Fiber Reinforced Cement (GRC) in Buildings (JGJ/T423-2018), Qinglong Group incorporated its thermal stress solution into the standard's formulation, proposing the "three principles of thermal stress verification": considering the superimposed effects of the annual maximum temperature difference, solar radiation temperature difference, and the shrinkage effect of the concrete base. In the Nanning ASEAN Culture and Art Center project, the curtain wall design guided by these principles withstood extreme temperature differences from -5℃ to 40℃, with no structural cracks appearing during 5 years of operation.

Facing the technical challenges of new building materials, Qinglong Group has always upheld the mission of "creating beautiful architecture," transforming thermal stress control technology into replicable industry solutions through 28 years of full-chain experience. From the micro-optimization of material formulations to millimeter-level control of construction processes, and from practical validation in landmark projects to the formulation and output of industry standards, Qinglong is leveraging its professional strength to advance GRC curtain wall technology toward greater safety, durability, and aesthetic value, providing solid technical support for balancing architectural envelope art with engineering safety.