The role of structural systems and building materials in sustainable post-expo use of World Expo pavilions

World Expos are international mega-events, organized to display the industrial achievements of countries while providing social and cultural involvement. Since the 1970s, they have focused on minimizing ecological problems and promoting sustainability with innovations in science and technology. However, due to their mega-scale and ephemeral nature, issues like building boom, oversized infrastructure, and abandoned pavilions have been observed throughout the years, which conflict with their sustainability theme.
Since the concerns for the post-event period are generally caused by the lack of initial planning for the post-expo usage, this thesis claims that one of the solutions is a concise configuration of structural systems and materials by considering the further use of pavilions. Therefore, this study aims to reveal what the role of structural system and material configurations is on a sustainable post-expo use. With this aim, the selected pavilions from the World Expos with sustainability-related themes are categorized based on their permanency or temporariness and analyzed regarding four categories of sustainability (functional, environmental, socio-cultural and economic). For the analysis, 15 sustainable features are determined to observe the characteristics of structural system and material configurations related to the post-expo use. Based on the number of sustainable features of each pavilion, the role of structural system and material configurations in post-expo use are evaluated. The results show that for permanent pavilions, structural systems and materials have no or low role in the sustainable post-expo use. On the contrary, they have a significant impact on the efficient post-expo use of temporary pavilions. It is concluded that the well-conceived configuration of structural systems and building materials equipped with innovative sustainable features would allow for more efficient use of resources while minimizing harmful impacts on the environment and reducing energy consumption in construction, dismantling, reusing, and recycling processes. The findings suggest that; in order for World Expos to overcome the issues that arise in the post-expo period, as well as the real-life sustainability problems, all four sustainability categories should be integrated together with the use of innovative solutions by considering the post-expo process in the pavilions' structural system design and material selection.