Gabon steel truss structure curved exhibition hall installation
Amidst the tropical ambiance of the west coast of Africa, a curved exhibition hall, blending streamlined aesthetics with industrial power, is rising from the ground, becoming a new window showcasing Gabon’s regional culture and commercial vitality. Yirong Steel Structure was deeply involved in this project, leveraging its precise control over complex curved structures and its end-to-end solution capabilities to perfectly integrate steel art with adaptability to the tropical climate, setting a benchmark for steel structure applications in large-scale overseas public buildings.
Curved Truss
The core structure of the exhibition hall utilizes a customized curved steel truss system, serving as the backbone of the entire project. Unlike traditional straight trusses, curved trusses require parametric design using 3D modeling software (such as Tekla Structures) to precisely calculate the curvature, angle, and stress distribution of each member. This ensures that the continuous curved surface from the ground to the roof satisfies both visual fluidity and structural mechanics requirements.
The truss main body is constructed using Q355B high-strength steel. Prefabricated in sections in the factory, it was assembled on-site using a total station for positioning and temporary support frames. The entire structure was finally joined together using a combination of high-strength bolts and welding.
During construction, the team specifically optimized the welding process for the high-temperature and high-humidity environment of the tropical region. Low-hydrogen welding rods were used in conjunction with windproof canopies, and interlayer temperatures were strictly controlled to ensure weld quality met first-class standards. Furthermore, all components underwent hot-dip galvanizing before leaving the factory, with a thickness exceeding 85μm, effectively resisting salt spray corrosion from the marine climate and guaranteeing a service life of over 25 years.
Galvanized C-shaped Steel Purlins
As key force-transmitting components connecting the truss and the enclosure system, the project selected customized galvanized C-shaped steel purlins. Considering the unique curvature of the arched roof, the Yirong technical team abandoned standard straight purlins. Instead, they pre-bent C-shaped steel into a shape matching the truss curvature using a cold-bending process, achieving a maximum single-piece length of 12 meters, thus reducing on-site cutting and splicing.
The purlin cross-section uses C200×70×20×2.5mm specifications, ensuring bending stiffness while reducing weight by 30% compared to traditional H-beam purlins, significantly reducing hoisting costs. For surface treatment, in addition to conventional hot-dip galvanizing, a weather-resistant coating is added to withstand Gabon’s annual average temperatures above 28°C and humidity levels above 80%, avoiding the risk of corrosion under long-term exposure.
During installation, self-tapping screws are used to fix the purlins to the truss web, with spacing strictly controlled within 1.2 meters. Combined with wind-resistant clamps and a tie rod system, a stable truss and purlin synergistic force-bearing network is formed, ensuring the roof maintains structural safety even under a Category 12 typhoon load.
Metal Panel Enclosure System
The enclosure system utilizes 0.8mm thick galvanized aluminum-zinc coated steel sheets (AZ150) with a silver-white fluorocarbon paint finish. This echoes Gabon’s abundant forest resources while highlighting a modern industrial style through its metallic texture. For the drainage requirements of the curved roof, the panels feature a 360° standing seam interlocking design (Type III), eliminating exposed screws. This not only enhances waterproofing but also creates a continuous, smooth curved surface on the roof panels, contrasting with the rigid lines of the trusses.
Yirong Solution
Faced with challenges such as long distances, significant standard differences, and complex construction environments in overseas projects, Yirong Steel Structure provides an integrated solution encompassing design, manufacturing, transportation, installation, and after-sales service. A technical team was dispatched to Gabon for on-site surveys, adjusting the design based on local material supply and construction conditions.
The manufacturing process leverages its own 100,000㎡ intelligent factory, enabling digital production and quality traceability for trusses, purlins, and metal panels. The transportation phase utilized a combination of 40-foot high-cube containers and framed containers, shipping directly to the Port of Gentil in Gabon via sea, with GPS monitoring throughout to ensure the components remained intact. During the installation phase, experienced Chinese engineers provided on-site guidance and trained local workers in high-altitude work safety regulations and new connection techniques, ultimately achieving the efficient goal of completing the main structure’s topping-out within three months.
Currently, the Gabonese arc-shaped exhibition hall is in its final stages, and its unique spatial form and reliable structural performance have been highly praised by the client. This steel truss structure not only demonstrates Yirong Steel Structure’s strength in the overseas market but also serves as another shining example of Chinese enterprises participating in African infrastructure construction, providing a replicable “Chinese solution” for the application of steel structures in large public buildings in tropical regions.
