Design of single-layer free-form steel structures: A case study on the british museum great court roof

Single-layer free-form systems have become increasingly popular in architectural design projects as they offer the opportunity to create unique and visually stunning structures. These designs have gained global attention due to their impressive appearance and ability to push boundaries creatively. Using single-layer systems is environmentally friendly and reduces construction waste by using less material than traditional construction methods. Nowadays, many architectural projects incorporate single-layer free-form systems to construct exceptional and one-of-a-kind buildings. This thesis comprehensively examines the technical details of single-layer free-form systems from architectural and engineering perspectives, including connection types such as rigid, semi-rigid, and hinged connections. The study thoroughly examines the welded and bolted connection details at the nodal points of single-layer free-form systems and their advantages and disadvantages. This thesis examines the architecture of the Queen Elizabeth II Great Court British Museum, considered one of Europe's most significant courtyard roof projects. The structure of a single-layer free-form building in Istanbul's Yeşilköy neighborhood, Bakırköy district, is analyzed using the SAP2000 program. The critical joint is also analyzed as a welded and bolted connection using Ansys for comparison. A uniform profile section is selected for the building's structural design to make the design more accessible. Various loads, including static loads, snow loads, earthquake loads, and wind loads, are numerically evaluated based on relevant codes such as Turkish Seismic Code (TSC 2018), Turkish Steel Structure Code (TSSC 2016), TS EN 1991-1-3:2009, and TS EN 1991-1-4:2005. Two different analysis cases are conducted for the single-layer free-form system under symmetric and asymmetric load combinations. The results are presented in tables and visual representations for comparative evaluations. The structural analysis indicates that the deflection values are similar, but the welded connection provides more stability compared to the bolted connection regarding torsion. The maximum stress calculated in the analysis of the welded connection is approximately 60% higher than that of the bolted connection. In comparison, the maximum deflection calculated in the bolted connection analysis is approximately 65% higher than that of the welded connection.