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Jianguo C.,Nanjing Southeast University | Xiaowei D.,University of California at San Diego | Yuting Z.,Nanjing Southeast University | Jian F.,Nanjing Southeast University | And 2 more authors.
Journal of Mechanisms and Robotics | Year: 2016

The folding behavior of a prismatic mast based on Kresling origami pattern is studied in this paper. The mast consists of identical triangles with cyclic symmetry. Bar stresses and necessary external nodal loads of the mast during the motion are studied analytically. The results show that the mechanical behaviors are different when the initial height of the mast is different. Then the numerical analysis is used to prove the accuracy of the analytical results. The influence of the geometry and the number of sides of the polygon on the folding behavior of the basic segment is also investigated. The folding process of the mast with multistories was discussed. The effect of the imperfection based on the eigenvalue buckling modes on the folding behavior is also studied. It can be found that when the number of sides of the polygon is small, the imperfection in the axial direction affects the energy seriously by changing the folding sequence of the mast. When the number of sides of the polygon is larger, the imperfection in the horizontal plane has significant effect on the folding pattern, which leads to the sudden change of energy curve. © 2016 by ASME. Source


Wang X.,Hefei University of Technology | Wang X.,Jiangnan University | Liu B.,Hefei University of Technology | Tian Y.,Hefei University of Technology | Qin Y.,Wuxi Architectural Design and Research Institute Co.
Journal of Earthquake Engineering and Engineering Vibration | Year: 2012

A study is conducted on the seismic behavior of three recycled concrete knee-joints with 100% recycled coarse aggregate under low frequency reversed load. The seismic behavior of recycled concrete members such as failure features,ductility, stress of steels in the specimens and energy dissipation under reversed loads is investigated. The test and analyses show that the recycled concrete member can be applied in structures because of its good seismic behavior. These specimens are modeled with ANSYS software. The calculated skeleton curves and the stress distribution of the specimen are corresponding well with the test results. It is found that the calculated shear capacity from formula provided in the code is significantly greater than test results. Source


Jianguo C.,Nanjing Southeast University | Xiaowei D.,University of California at San Diego | Ya Z.,Wuxi Architectural Design and Research Institute Co. | Jian F.,Nanjing Southeast University | Yongming T.,Lulea University of Technology
Journal of Mechanical Design, Transactions of the ASME | Year: 2015

The deployment of a cylinder based on origami with Kresling pattern, whose basic mechanisms are formed by the buckling of a thin cylindrical shell under torsional loading, is studied in this paper. The model consists of identical triangular panels with cyclic symmetry and has a small displacement internal inextensional mechanism. First, geometric formulation of the design problem is presented. Then, assuming that the deployment and folding process is uniform, the bistable behavior of the cylinder is discussed. It can be found that, during the deployment, the dimensionless strain energy increases first and then reduces to zero but followed by another sharp increase. Moreover, the limit condition of geometry parameters for the bistable phenomenon is also discussed. Finally, the bistable behavior is also studied by using numerical simulations for simple and more complex case of the cylinder with multistory. The numerical results agree well with the analytical predictions. Therefore, comparisons with finite element predictions have shown that the analytical solutions given in this paper are accurate and have validated the assumptions made in the derivations. Copyright © 2015 by ASME. Source


Cai J.,Nanjing Southeast University | Deng X.,University of California at San Diego | Feng J.,Nanjing Southeast University | Zhou Y.,Wuxi Architectural Design and Research Institute Co.
Smart Materials and Structures | Year: 2015

The folding and deployment of a cylinder with Miura origami patterns are studied in this paper. First, the geometric formulation of the design problem is discussed. Then the loading case of the axial strains and corresponding external nodal loads applied on the vertices of the top polygon during the motion is investigated analytically. The influence of the angle between the diagonal and horizontal fold lines α and β and the number of Miura origami elements n on the dynamic behavior of the basic segment is also discussed. Then the dynamic behavior is analyzed using numerical simulations. Finally, the deployment process of a cylinder with multi-stories is discussed. The numerical results agree well with the analytical predictions. The results show that the range of motion, i.e. the maximal displacement of top nodes, will also increase with the increase of angles α and β. This cylinder, with a smaller n, may have a bistable behavior. When n is larger, the influence of n on the axial strains and external nodal loads is slight. The numerical results agree well with the analytical predictions. Moreover, the deployment of the cylinder with multi-stories is non-uniform, which deploys from the upper story to the lower story. © 2015 IOP Publishing Ltd. Source


Cai J.,Nanjing Southeast University | Zhang Y.,Nanjing Southeast University | Xu Y.,University of Strathclyde | Zhou Y.,Nanjing Southeast University | And 2 more authors.
Journal of Mechanical Design, Transactions of the ASME | Year: 2016

Foldable structures, a new kind of space structures developed in recent decades, can be deployed gradually to a working configuration and also can be folded for transportation, thus have potentially broad application prospects in the fields of human life, military, aerospace, building structures, and so on. Combined with the technology of origami folding, foldable structures derive more diversified models, and the foldable structures in cylindrical shape are mainly studied in this paper. Some researchers use the theory of quaternion representing spatial fixed-point rotation and construct the rotating vector model to obtain the quaternion rotation sequence method (QRS method) analyzing origami, but the method is very limited and not suitable for the cylindrical foldable structures. In order to solve the problem, a new method is developed, which combines the QRS method and the dual quaternion method. After analyzing the folding angle via the QRS method for multivertex crease system and calculating the coordinates of all vertices via the dual quaternion, the rigid foldability can be checked. Finally, two examples are carried out to confirm validity and versatility of the method. Copyright © 2016 by ASME. Source

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