CURRENT: OPTIMIZATION OF PRESSURIZED MEMBRANES UNDER STORM SURGE LOADING

The purpose of coastal structures is to shield civil infrastructure along shorelines from the impact of storms. Current hard coastal structures (such as seawalls) obscure real estate sightlines, inhibit commercial and recreational activities and have high environmental and economic costs.

We generate a new understanding of how the behavior and design of large-scale pressurized membrane structures can be characterized and optimized to effectively respond to extreme storm surge loading. Pressurized flexible surface systems are especially suited to resist extreme loads since they redistribute these loads over their entire three-dimensional surface. Made of rubber-coated nylon fabrics such barriers can be designed and constructed for a shorter lifespan to account for projected yet uncertain changes in storm behavior. They can also be stowed and deployed as needed and thus not hinder real estate sightlines or human activities.

This study is challenging due to the large unprecedented scale of the pressurized membrane barrier, the extreme magnitude of the loading, the absence of engineering design codes for such application and the unknown three-dimensional interaction between the non-linear barrier and the fluid loads. The interpretaion of the results of computational fluid/structure interaction models generates knowledge of the response of membranes subjected to extreme temporally and spatially varying loading conditions and further increase knowledge in this unexplored research domain in solid mechanics and lightweight structures design. We are currently working to establish the effects of initial shape, internal pressure and thickness on the structural response of pressurized membrane barriers when loaded and on the optimum design of the membrane.