How to Adjust the Connection Angle of Double-Curved GRC Panels with Steel Structures? Flexible Connection and Dynamic Adaptation Technology

The connection between double-curved GRC panels and steel structures is by no means a simple rigid fixing; instead, it requires a "flexible connection system" capable of accommodating three-dimensional deviations, thermal deformation, and minor structural movements. The ability to adjust connection angles is the core of this system. The patented 3D adjustable connectors developed by Qinglong Group achieve linear adjustment of ±10mm to ±20mm along the X, Y, and Z axes, as well as rotational adjustment around the connection point within a certain angle, perfectly resolving the complex spatial relationship issues between double-curved panels and steel structure base surfaces caused by construction tolerances, thermal expansion and contraction, and dynamic loads.

Achieving adjustment relies on carefully designed connection nodes. A "transition connector system" is typically used: one end is securely connected to the GRC panel via embedded parts or undercut anchors, while the other end attaches to connection plates welded onto the steel structure through slotted holes and grooves, fitted with leveling bolts and washers. The slotted holes and grooves provide adjustment margin within the plane (X and Y directions); screwing the leveling bolts in and out enables precise adjustment in the depth direction (Z direction). Where angular compensation is required (for example, when the normal direction of a double-curved panel is not perpendicular to the steel structure surface), "spherical hinge connectors" or a "double-bolt parallelogram mechanism" can be adopted, allowing the connection point to rotate freely within a certain cone angle range.

Adjustment must be carried out under a controlled process. First, a total station is used to perform 3D scanning of the completed structural base surface to obtain actual coordinate data, which is compared with the BIM design model to calculate the deviation between the theoretical and actual positions of the connection points of each GRC panel. Then, during factory prefabrication or on-site assembly, the connectors are pre-adjusted according to the deviation values. During installation, panels are first roughly fixed, then finally fine-tuned under the guidance of laser instruments; only after the installation angles of all panels conform to the designed curved surface are all bolts finally tightened. In a special-shaped venue project in Shenzhen, we applied this technique to successfully and precisely install hundreds of double-curved panels on a spatially twisted steel reticulated shell, achieving a high degree of unity between design and construction.