Form-finding analysis of cable-membrane tensile structure with outer ring truss

For a flexible tension structure, the first thing to do is to perform a form-finding analysis to obtain a reasonable initial state of the structure. The initial state includes the structure's own weight and the cable force distribution under the additional dead load and the corresponding geometric configuration. The geometric configuration and expectations must be ensured to be consistent with the geometry of the building. This paper used the MIDAS software to first establish the zero-state model of the structure, and then added reasonable prestress to ensure that the initial configuration of the structure under prestress, structure dead weight and additional dead load is basically the same as that under zero state, thus ensuring the feasibility and accuracy of later structural load analysis and construction process analysis, and providing ideas and methods for related projects.

Membrane Structures with Half-Costa Surface in YZ-Plane

This paper presents the computational form-finding analysis of half-Costa tensioned membrane structure model in YZ-plane with different boundaries. The computational form-finding analysis is carried out based on nonlinear analysis method. The tensioned membrane structure in the form of half-Costa models in YZ-plane with different geometry have been found to converge with least square error of total warp and fill stress deviation. The outcome of this paper can serve as a reference in selecting satisfactory parameters to allow the performance increase of tensioned membrane structure in the form of half-Costa in YZ-plane respected to their boundary condition. These models will be selective forms of tensioned membrane structure for design engineers and architect to ponder on as it is a resource efficient structure hence preventing further damage to the environment.

Computational Form-Finding Analysis in Richmond’s Surface with Different Prestress

Form-finding of fabric surface bordered by Richmond’s has been investigated. In this study, the possibility of adopting the form of Richmond’s as surface shape in tensioned fabric structure under different prestress values has been studied. The combination of shape and internal forces for the purpose of stiffness and strength is an important feature of fabric surface. For this purpose, form-finding needs to be carried out. Nonlinear analysis method has been used for form-finding analysis of the fabric in the form of Richmond’s minimal surface. Richmond’s minimal surface models are analyzed with two different values of prestress which are 3000N/m and 5000N/m. The average warp and fill stresses deviation for all models presented are less than 0.01 which indicates the model can serve as reference to the engineers or architects in the selection of proper surface parameter to achieve a structurally viable surface. As a result, this study is expected to lead the improvement of rural basic infrastructure, economic gains, sustainability of built environment and green technology initiative.

Form-Finding Analysis of a Class 2 Tensegrity Robot

In this paper, a new form-finding analysis methodology for a class 2 tensegrity robot is proposed. The methodology consists of two steps: first, the analysis of the possible geometric configurations of the robot is carried out through the results of the kinematic position analysis; and, second, from the static analysis, the equilibrium positions of the robot are found, which represents its workspace. Both kinematics and static analysis are resolved in a closed-form using basic tools of linear algebra instead of the strategies used in literature. Four numerical experiments are presented using the finite element analysis software ANSYS©. Additionally, a comparison between the results of the form-finding analysis methodology proposed and the ANSYS© results is presented.

Form-Finding Analysis of the Rail Cable Shifting System of Long-Span Suspension Bridges

The determination of the non-loading condition of the rail cable shifting (RCS) system, which consists of the main cables, hangers, and rail cables, is the premise of girder erection for long-span suspension bridges. An analytical form-finding analysis model of the shifting system is established according to the basic assumptions of flexible cable structures. Herein, the rail cable is discretized into segmental linear cable elements and the main cable is discretized into segmental catenary elements. Moreover, the calculation and analysis equations of each member and their iterative solutions are derived by taking the elastic elongation of the sling into account. In addition, by taking the girder construction of the Aizhai suspension bridge as the engineering background, a global scale model of the RCS system is designed and manufactured. The test system and working conditions are also established. The comparison between the test results and analytical results shows the presented analytical method is correct and effective. The process is simplified in the analytical method, and the computational results and precision satisfy practical engineering requirements. In addition, the proposed method is suitable for application in the computation analysis of similar structures.

Form-Finding Analysis on the Rail Cable Shifting System of the Long Span Suspension Bridges

The determination of the non-loading condition of the rail cable shifting (RCS) system, which consists of main cables, hangers and rail cables, is the premise of the girder erection for the long-span suspension bridges. An analytical form-finding analysis model of shifting system is established according to the basic assumptions of flexible cable structures. Herein, the rail cable is discretized into segmental linear cable elements and the main cable is discretized into segmental catenary elements. Moreover, the calculation and analysis equation of each member and their iterative solutions are derived by taking the elastic elongation of the sling into account. In addition, by taking the girder construction of Aizhai suspension bridge as engineering background, a global scale model of the RCS system is designed and manufactured; also the test system and working conditions are established. The comparison between the test results and analytical results shows the presented analytical method is correct and effective. The process is simplified in the analytical method, and the computational results and precision can satisfy the practical engineering requirements. In addition, the proposed method is suitable to apply to the computation analysis of similar structures.