| Foldable space structure of five rectangular arc is a new space structure, which Having reusable, folded small volume, a large space for internal use after expand, and other significant characteristics of economic, aesthetic, easy to transport, so it can be widely used in civil and military engineering. This structure is light, and whose span is large. Meanwhile, it consists of many bars and the hub nodes connection is complex, so snow load on to become one of the main considerations when designing of such structu--re. But the structure of such studies have not been reported at home and abroad, they failure modes under snow loads, transfer mechanism of hub nodes is unclear, and Also does not have a special computer program which dedicated multi-scale numerical calculation can carries on the analysis and calculation. In this paper, the main research contents and results as follows:1. Full-scale static test on the Foldable Space Structure of five Rectangular arc is completed under the function of own weight and full cross snow load. The displacement measuring results show: Under the load, the displacement deformation curve of grid structure show the characteristics of High in the middle and low on both sides, in additi--on, the curve Symmetry is good. the displacement deformation curve in the long axis direction is symmetrical about the axis of G,and the curve in the short axis is also sym--metrical about the long axis which consists of six hub node:B3、D3、F3、H3、K3、M3. When the snow thickness attained 0.14 m, G4 hub node decreases 178 mm which is the maximum vertical displacement;G2 hub node moves to the outside of the structure with 101 mm which is the maximum short-axis direction of the horizontal displacement.2. The test result of strain measurement indicates that the turning of G2,G3 hub nodes caused by the continuous pressing of heads of bar parts connecting to them. Among all the factors, internal force of bar parts of G2’H2、G2’F2 is the major contributor of G2 turning, while the forces from the top of G3F3’、G3H3 is responsible for that of G3.3. The damage of foldable space structure of five rectangular arc is caused by the broken in connecting section between hub nodes in the climbing units. As the materials of hub nodes are vulnerable towards shaping, they cannot entirely eliminate the cracking of metal pieces in the metal pieces on the top of bars. With the growing pressure, axial strain within binding parts of hub nodes increases accordingly. At the same time, hub nodes turn in the process of such pressing. When the loading reaches a level of 0.14 m, these metal pieces will suffer from extreme bending and stick to the inner side of hub nodes. Mineral cracks can be observed as the rotation additional moment has become so excessive that the grid structures can no longer support the whole system.4. The test results show that the volume of strain is approximately 23%. As a result, skipping the binding moment effects will cause considerable deviation while measuring and modeling the grid structures.5. This essay briefly conducts stiffness matrices within the grid structures, and modulates related finite element calculation program. The essay then accomplishes the calculation tasks for numerical analysis of five-folding truss arch moment under the experimental loading strains. Further comparisons between experimental results and calculation outcomes are also provided. The result is as follows: the program responses well to the assessing the values of bending and axial stress of the grid structure. |
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