A new model is proposed to accurately predict the wrinkling and collapse loads of a membrane inflated beam.In this model,the pressure effects are considered and a modified factor is introduced to obtain an accurate prediction.The former is achieved by modifying the pressure-related structural parameters based on elastic small strain considerations,and the modified factor is determined by our test data.Compared with previous models and our test data,the present model,named as shell-membrane model,can accurately predict the wrinkling and collapse loads of membrane inflated beams.
In this paper,the wrinkle-crease interaction behavior of a rectangular membrane under edge tension is simulated.The creased membrane is modeled by using a Modified Two-Parameter model.In this model,two crease parameters,i.e.the effective modulus of creased membrane and the residual stress from creasing,are computed by using MacNeal's method that was firstly applied directly in a flat membrane with the local crease.We have proposed a method to solve the wrinkling computing issue of the creased membrane by using a Direct Perturb-Force technique in our previous work.Based on our method,the effects of crease location on the wrinkle-crease interaction behavior can be evaluated accurately.These results will be of great benefit to the analysis and the control of the wrinkles in the membrane structures.
Wrinkling analysis of a rectangular membrane with a single crease under shearing is performed to understand the wrinkle-crease interaction behaviors.The crease is considered by introducing the residual stresses from creasing and the effective modulus into the baseline configuration with assumed circular cross-sectional crease geometry.The wrinkling analysis of the creased membrane is then performed by using the direct perturb-force(DP) simulation technique which is based on our modified displacement components(MDC) method.Results reveal that the crease may influence the stress transfer path in the membrane and further change the wrinkling direction.The crease appears to improve the bending stiffness of the membrane which has an effective resistance on the wrinkling evolution.The effects of the crease orientation on wrinkle-crease interaction are studied toward the end of this paper.The results show that the wrinkling amplitude,wavelength,and direction increase as the crease orientation increases,and the wrinkling number decreases with the increasing crease orientation.These re-sults will be of great benefit to the analysis and the control of the wrinkles in the membrane structures.
C.-G.Wang.H.-F.Tan.X.-D.He Center for Composite Materials,Harbin Institute of Technology,150080 Harbin,China Post-doctoral Research Center in Material Science and Engineering,Harbin Institute of Technology,150001 Harbin,China
