| Foldable space structuer of five rectangllar arc is a new symmetric deployable structure.Foldable space structuer have internal kinematic mechanisms.Thus,these structures satisfy the hard conditions of time or space,the structure is widely applied into field training and military operations,earthquake relief,etc.In fact,deployable structures have many inportant advantages,for example,reusable and quick-fold.Owing to its small height and weight,obvious deformation of the bar and node displacement under the snow and wind load was taken on.Yet the study on its bearing performance is smaller,the displacement and stress of the folded grid structure under load are not clear.The main content and achievement is as follows:A test on its bearing performance under the snow load was completed.Analysis results showed as follows:(1)under the snow load was taken on.The structure of the structure moves downward,and the two sides of the structure extend outwards.The max horizontal displacement was at the edge of the structure of common grade unit in A2,A5,N2,N5 node,the maximum value is 75.0mm.(2)The distance between the hub disk node has changed.The climb unit has the larger change,the G3-G4 hub plate of the distance between the nodes biggest change,shorten the 180.0mm(that is,the angle of the rod is larger).(3)Those hubs influnced on the bending stress of those bars weakly but strongly on the force of the axial attraction.The structure produces a large bending stress,the axial stress is relatively small.A-axis and G-axis rod bending deformation mainly occurred to the outside.A test on its bearing performance under the 90° wind load and 0° wind load was completed.Analysis results showed as follows:(1)Under the 90° wind load,The displacement of the whole structure is mainly in the minor axis direction,displacement of A5 node reached 172.2mm.the length of the top unit and the leeward side member is larger.Among them,the distance between A5-A6 and G3-G4 hub plate increases by 158.0mm,102.0mm.The windward side bar is mainly pulled to the outside of the structure,and the leeward side bar is mainly pulled toward the inside of the structure.(2)The structural hub node is significantly increased along the long axis under the 0° wind load was taken on.Compared with other load,the axial force and bending moment of the member are smaller,the maximum bending moment of A3'Q1 is 8000.00N·mm.A test on its bearing performance under the interaction of the snow load and the 90°,0° wind load were completed.Analysis results showed as follows:(1)Under the action of snow load and 90° wind load,The direction of the vertical displacement of the joint on the east side of the structure is changed,the top unit node has the largest displacement,G3 node displacement is 259.0mm.The distance between A5-A6 and G5-G6 hub plate increases by 107.0mm and 188.0mm,respectively.The side member of the leeward side has been bent to the outside,the deformation is larger when the snow load is applied,and the deformation decreases when the wind load is applied;the bending direction of the side member is the same as that on the leeward side Under the action of snow load,when the wind load is applied,the deformation direction of the windward side member is changed,the windward side member gradually changes from the outside to the inside.(2)Under the action of snow load and 0° wind load,The displacements of the structural climbing unit nodes in three directions are larger.The extension of the bottom element member is larger,and the distance between the A1-A2 hub nodes is 274.0mm.The axial force and bending moment on the south side bars and gable bars are greater than those on the North side,The axial force of the climbing unit is obviously larger than that of the bottom element. |
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