Design and construction of catenary-ruled surfaces

The past two decades have witnessed an increasing adoption of double-curved surfaces in architectural design and building construction. However, their shape complexity has brought a great challenge in design and construction, typically leading to high modeling and construction costs. In this study, a new geometry family, termed catenary-ruled surface, is proposed. They can be conveniently created using catenary rulings based on the transformation of line rulings, thereby offering new possibilities for designing a wide variety of architectural forms. Moreover, this paper uses a physical model to demonstrate that a specific group of catenary-ruled surfaces can be effectively and inexpensively constructed using a proposed string actuation system. This is achieved by using a series of foldable arches to form the target surface, with their folding motion controlled by simply pulling external strings. The constructed structure with catenary rulings can act as an efficient structural system that is predominantly under pure compression.