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Current technologies and trends of retractable roofs

In recent years, retractable roofs have become a popular feature in sport stadiums. However, they have been used throughout time because they allow a building to become more flexible in its use. This thesis reviews the current technologies of retractable roofs and discusses possible innovations for the future. Most retractable roofs use either a 2-D rigid panel system or a 2-D membrane and I-D cable system. These structures can be seen throughout the world. Designing retractable/deployable systems involves evaluating the structural features and opening and closing features to determine what is appropriate for a particular building. Common issues for designing these structures are summarized. Current retractable roof research is commonly incorporated within the field of deployable structures. The word deployment means the act of unfolding or opening while retraction is the opposite (Pellegrino 2001). Pantograph structures along with other bi-stable structures are being researched to find new configurations that could be used for civil applications. Small-scale models have been produced but large-scale models still need to be developed to help progress the research. The paper will conclude with the case studies of two roofs, one being Toronto's Sky Dome and the other being the Gerry Weber Tennis Center.