How to Ensure Structural Stability in Large-Span GRC Shapes?

Ensuring the structural stability of large-span GRC shapes is a systematic undertaking involving "wind-resistant form design, internal reinforcement construction, support system coordination, and precise installation." Its goal is to resist wind loads, self-weight, temperature effects, and accidental loads, while avoiding instability failure. In major projects, Qinglong Group ensures the safety and aesthetics of large-span GRC shapes through optimized "form-force integration" design and rigorous engineering control.

Achieving form resistance by exploiting the shape's own characteristics is the ideal approach. For large-span GRC shapes such as arches and shells, priority should be given to spatial curved forms that work primarily in compression, making full use of concrete's excellent compressive performance. Through rational form-finding analysis, the shape should be kept, under primary loads, as close as possible to a membrane stress state with zero or minimal bending moment, thereby achieving large spans with a relatively thin thickness. This is the most economical and effective way to ensure stability.

Internal reinforcement and framework support are the technical keys. When the shape cannot achieve complete self-stability, reinforcing structures must be provided inside or on the back of the GRC panels. These mainly include: 1) Setting reinforcement ribs: arranging crisscrossing rib grids on the back of the panels to form cross-beam or closely ribbed structures, significantly improving overall stiffness and bending resistance. Rib dimensions and spacing must be determined through calculation. 2) Built-in steel frameworks: for components with large cantilevers and heavy wind loads, a spatial truss made of embedded structural steel or steel tubes is often placed inside the GRC, with the steel framework carrying the primary loads while the GRC serves as the enclosure and decorative surface layer. This composite structure can greatly enhance spanning capability.

Coordination with the main support system is crucial. Large-span GRC shapes must transfer loads to the main structure through a reliable connection system. The position and number of support points must be optimized through finite element analysis to ensure a clear load path. Connection joints must be designed to both carry loads and release thermal deformation, avoiding excessive restraint stresses. During installation, precise measurement and positioning as well as strict construction monitoring are required to ensure the final formed state is consistent with the design model. In major projects, Qinglong commonly uses BIM technology and 3D scanning for full-process quality control, ensuring that the structure of large-span GRC shapes is absolutely secure.