Finite element simulation of deployment of large-scale confined inflatable structures

Abstract

Large-scale inflatable structures have become a viable alternative for sealing and isolating segments of large-diameter conduits or tunnel sections to prevent the propagation of flooding, noxious gases or smoke. In such applications, the inflatable structure is prepared for placement, either permanently or temporary, and left ready for deployment, inflation, and pressurization when needed. Once deployed and in operation, the level of sealing effectiveness depends on the ability of the inflatable structure to deploy and self-accommodate, without human intervention, to the intricacies of the perimeter of the conduit being sealed. This work presents finite element evaluations of the deployment and inflation of a full-scale inflatable plug placed within a tunnel section. Folding sequences and controlled deployment techniques developed experimentally served as the basis for the development of finite element models that can simulate different stages of folding, placement, initial deployment and full inflation of the structure. The good level of correlation between experimental and simulation results in terms of deployment dynamics, levels of contact as well as number and position of zones with no contact in the confining perimeter, demonstrate that the proposed modeling strategy can be used as a predicting tool of the behavior of a large-scale inflatable structure for a given confining environment.