298 CONFERENCE 6.—8.9.2017 TU-BERLIN 298 ORIGAMI INSPIRED DEPLOYABLE & MOVABLE BRIDGE FOR DISASTER RELIEF Ichiro ARIO Ass. Professor, Dr. Hiroshima University Higashi-hiroshima, Japan mario@hiroshima-u.ac.jp Yuta HAMA Ph.D student Hiroshima University Higashihiroshima, Japan m174768@hiroshima-u.ac.jp Yuki CHIKAHIRO Ass. Professor, Dr. Shinshu University Nagano, Japan chikahiro@shinshu-u.ac.jp Kotaro ADACHI Ph.D student Hiroshima University Higashihiroshima, Japan m164305@hiroshima-u.ac.jp Andrew WATSON Ass. Professor, Dr. Loughbbrough University Loughbbrough, U.K. A.Watson@lboro.ac.uk Summary Using the latest technical developments in structural engineering, the basic mechanisms of the buckling and post-buckling response of a thin cylindrical shell under torsional or compression loading are reviewed. The deflection response deep into the large-deflection range is considered such that the shell is allowed to fold into a flat two dimensional form, via a mechanism reminiscent of a deployable or folding structure. The critical and initial post-buckling of Origami-folding effects are explored using the concepts of energy minimization and hidden symmetries. The concept is developed using Origami that is applied to a rapidly deployable, foldable, and movable bridge systems for multipurpose uses, predominantly in disaster relief for refugees and displaced people, is investigated. The concept for the structure has been inspired from Origami understanding and applying a scissors mechanism, a principle using linked, folding supports in a criss-cross 'X' pattern as a basic unit in the structural system. We review this new type of bridge system resulting in the Mobile bridge proposition which has the advantages of both simultaneously serving the specific purpose of providing relief for displaced people in times of need and in emergency situations. Keywords: deployable bridge; scissors-type bridge; emergency bridge; light-weight structure; temporary bridge 1. Utilising the art of Origami in the field structural engineering Buckling is recognized as one of the fundamental problems of elastic stability because of its significance in the engineering design of, for example, a thin circular cylindrical shell under torsion and/or axial compression will experience a sudden reduction in stiffness at the onset of buckling. The two contrasting loading situations exhibit quite different characteristics of load/deflection response as deformation continues into the large-deflection range. While the former initially results in a highly unstable response followed by re- stabilization as it settles into a localized form of the well-known Yoshimura or diamond pattern deformation, the latter forms similar but oblique shapes which are capable of folding entirely in the axial direction without significant in-plane stretching. Fig. 1 shows the development of the folded form in a paper specimen twisted between two inner plastic mandrels. Following an initial buckling stage that involves both bending and membrane (in-plane) stretching, a pattern resembling an Origami type mechanism is generated. Such folding is prevented in the axially loaded problem which has Yoshimura type pattern due to the significant stretching DOI: 10.24904/footbridge2017.09340