The report contains an assessment of current shell analysis capability. The assessment is based on work conducted at the Lockheed Palo Alto Research Laboratory under contract to the Air Force Flight Dynamics Laboratory. In addition to surveying the open literature, information for the study was gathered during a series of visits made to organizations throughout the United States at which there is an active shell analysis research effort. More than 40 industrial concerns, government agencies and universities have been visited to date. During each visit, technical personnel working in the area of shell analysis were interviewed to determine the scope of their present analysis capability, to learn of current research activities and to discuss computer methods of shell analysis in general. Information so obtained is summarized in a series of briefs which appear in the Appendix of this report.

*** Featuring a foreword by Pritzker Prize Winner Shigeru Ban *** Bringing together experts from research and practice, Shell Structures for Architecture: Form Finding and Optimization presents contemporary design methods for shell and gridshell structures, covering form-finding and structural optimization techniques. It introduces architecture and engineering practitioners and students to structural shells and provides computational techniques to develop complex curved structural surfaces, in the form of mathematics, computer algorithms, and design case studies. • Part I introduces the topic of shells, tracing the ancient relationship between structural form and forces, the basics of shell behaviour, and the evolution of form-finding and structural optimization techniques. • Part II familiarizes the reader with form-finding techniques to explore expressive structural geometries, covering the force density method, thrust network analysis, dynamic relaxation and particle-spring systems. • Part III focuses on shell shape and topology optimization, and provides a deeper understanding of gradient-based methods and meta-heuristic techniques. • Part IV contains precedent studies of realised shells and gridshells describing their innovative design and construction methods.

Shell structures are widely used in the fields of civil, mechanical, architectural, aeronautical, and marine engineering. Shell technology has been enhanced by the development of new materials and prefabrication schemes. Despite the mechanical advantages and aesthetic value offered by shell structures, many engineers and architects are relatively unacquinted with shell behaviour and design. This book familiarizes the engineering and architectural student, as well as the practicing engineer and architect, with the behaviour and design aspects of shell structures. Three aspects are presented: the Physical behaviour, the structural analysis, and the design of shells in a simple, integrated, and yet concise fashion. Thus, the book contains three major aspects of shell engineering: (1) physical understanding of shell behaviour; (2) use of applied shell theories; and (3) development of design methodologies together with shell design examples. The theoretical tools required for rational analysis of shells are kept at a modest level to give a sound grasp of the fundamentals of shell behaviour and, at the same time, an understanding of the related theory, allowing it to be applied to actual design problems. To achieve a physical understanding of complex shell behaviour, quantitative presentations are supplemented by qualitative discussions so that the reader can grasp the `physical feeling' of shell behaviour. A number of analysis and detailed design examples are also worked out in various chapters, making the book a useful reference manual. This book can be used as a textbook and/or a reference book in undergraduate as well as graduate university courses in the fields of civil, mechanical, architectural, aeronautical, and materials engineering. It can also be used as a reference and design-analysis manual for the practicing engineers and architects. The text is supplemented by a number of appendices containing tables of shell analysis and design charts and tables.

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

The increasing use of composite materials requires a better understanding of the behavior of laminated plates and shells. Large displacements and rotations, as well as shear deformations, must be included in the analysis. Since linear theories of shells and plates are no longer adequate for the analysis and design of composite structures, more refined theories are now used for such structures. This text develops, in a systematic manner, the overall concepts of the nonlinear analysis of shell structures. The authors start with a survey of theories for the analysis of plates and shells with small deflections and then lead to the theory of shells undergoing large deflections and rotations applicable to elastic laminated anisotropic materials. Subsequent chapters are devoted to the finite element solutions and include test case comparisons. The book is intended for graduate engineering students and stress analysts in aerospace, civil, or mechanical engineering.