Effect of temperature on the mechanical performance of plywood used in membrane-type LNG carrier insulation systems

Abstract

In this study, the mechanical performance of melamine–urea–formaldehyde (MUF) resin plywood composed of an orthotropic material, which is used as a structural material in liquefied natural gas (LNG) cargo containment systems (CCSs), is evaluated. With a decrease in temperature, the plywood changes from ductile to brittle under compressive loads; thus, it may fail to distribute the compressive loads caused by sloshing impact as well as lose its stiffness, which helps maintain the shape of the structure. However, only a few studies investigated the mechanical characteristics of MUF resin plywood under compressive loads caused by sloshing impact as well as the crack propagation and change in material features with decreasing temperatures. Therefore, the present study investigated the mechanical performance of MUF plywoods of different thicknesses under different temperatures and grain orientation parameters. The results indicate the mechanical properties of MUF plywood for compression with decreasing temperatures. Furthermore, based on thermomechanical analysis, this study shows that the critical temperature at which the plywood material tends to transition from ductile to brittle behavior is − 110 °C. This finding will help in the design of MUF plywood-based LNG CCSs considering its low-temperature brittleness.