Study on Flexural Properties of Tubular Underwater Inflated Structures Filled with Hydrogel Beads

  • Yanjun Li
  • Radivoje Stankovic
  • Bing Ouyang
  • Tsung-chow Su
Keywords: Underwater inflatable structure; Inflated structure; Flexural property; Hydrogel beads.


Underwater inflatable structures (UISs) are distributed in an initial folded state for ease of transportation and deployment. They are able to morph into their intended geometry upon arrival at their destination. This morphing/inflation process can be driven by hydrogel beads, which swell when they contact water. In this research, we study the physical characteristics of tubular UISs with different configurations (length, slenderness, beads density). We fabricated sets of tubular UISs with nylon sleeves filled with different amounts of hydrogel beads and built a flexural test platform mounted on the test tank for the bending experiment. This work provides the experimental Young’s modulus of the tubular UISs under elastic and plastic deformations, and also discusses how the different configurations contribute to the tubular UIS’s stiffness.