Experimental investigation on forming design methods of ETFE cushion structure

Abstract:

Two design methods of ETFE cushion were presented which are the three-dimensional patterning based on zero-stress state and the flat-patterning based on nonlinearity of ETFE material. The state definitions and mechanical models were defined for the two methods, respectively. Experiments and numerical simulations were performed to obtain the shapes, stress distributions and the variations. It is found that, for the three-dimensional patterning model, the maximum difference of the shapes between experimental and numerical results is 4 mm and the difference of the stress distribution is 0.4 MPa. For the flat-patterning model, a good agreement between the experimental and numerical results is obtained for the initial shape and it is obtained that the stress distribution decreases while the shape and the ratio of rise to span increase due to the creep properties of ETFE materials. These findings have validated the proposed forming design methods.