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หลั งคาเปลื อกบางและโครงสร้าง ๓ มิ ติ ชนิ ดอื่ น ๆ 26 The Journal of the Royal Institute of Thailand Vol. 39 No. 2 April-June 2014 บรรณานุกรม อรุณ ชัยเสรี... “เกร็ดความรู้เกี่ยวกับการควบคุมงานก่อสร้างอาคารคอนกรีตเสริมเหล็ก” ปรับปรุงครั้งที่ ๔ Abstract Thin Shells and Other Space Structures Arun Chaiseri Fellow of the Academy of Sciences, The Royal Institute, Thailand A large roof covering a very large area without undesirable interior col - umns usually requires a 3-dimensional structure such as a thin shell which has various shapes and sizes. In choosing the most appropriate one, the available vertical space, the atmospheric as well as environmental condition of the surrounding area should be carefully considered. A thin-shell roof usually means a reinforced concrete structure having very small thickness compared with the other two dimensions. In designing a double-curvature shell, “membrane theory” is normally applied, where the thin curved concrete slab is treated like a large membrane which can take only tensile force; while the compression force is carried to the foundation through compression members. Other 3-dimensional structures popularly used nowadays are space frames or space trusses. The members of the lattice-like structures are made of structural steel or steel pipes joined together by welding or steel balls. They may be fabricated from a far away factory and shipped to the construction site and are assembled on the floor right under the roof space. The whole assembly is then simultaneously lifted upward to sit on preconstructed columns and finally cover the whole roof structures with proper roofing materials such as metal sheets. Still other 3-dimensional structures are pneumatic structures, waffle slabs, hanging structures or their combinations. To obtain the most appropriate 3-D structure to suit a building, the following factors should be carefully studied. The first things to be considered are the strength and safety, followed by aesthetics of the building as well as its required functions, while the most important factor is the cost of construction which should not overrun the budget. Otherwise, the project might not be feasible. Keywords: thin shell, membrane theory, hyperbolic paraboloid, 3-dimensional structure, space frame, S.A.F.E.