An Experimental Investigation of Inflatable Fabric Beams of Floating Composite Causeway

Abstract

Inflated membrane structures make of high-strength fabric material that can be used as beams when inflated at high internal pressure. Due to their physical characteristics which are deployed and lightweight, they can be used as off-shore floating structures such as floating breakwaters and floating causeways. The paper is devoted to present experimental studies on the behavior of fabric inflated beams. The experimental result was compared with wrinkling theory. This experiment consisted of three parts. First, the beams were tested under bending load with different internal pressures and then the different diameters specimens were tested with identical pressure. The results showed that the deformation depended on the applied load, the internal pressure and the diameter. The amount of deformation increased sharply when the local wrinkles occurred and the load-displacement curve manifested strong nonlinearity. Then, an experiment of the parallel-connected beams was performed to obtain the parallel-connected effect of the load-deflection response of inflated beams. The results showed the deflection of the single beam was not twice of the deflection of double parallel beams. A floating causeway model experiment was also finished, the results confirmed the previous conclusions and the floating composite causeway was enough stable. These experimental results can be applied to provide theoretical guidance and scientific basis for design method of the floating composite structure.