Structural behaviour of a prefabricated composite wall system made from rigid polyurethane foam and Magnesium Oxide board

This paper presents the structural behaviour of an emerging prefabricated wall system made up of glass fibre reinforced rigid polyurethane foam (PUF) and Magnesium Oxide (MgO) board. Full-scale wall specimens were prepared and tested under transverse bending, compression and shear. The results of the experimental investigation showed that the behaviour of the composite walls is governed by the strength of the MgO board. A complete interaction between the rigid PUF and MgO board was achieved using epoxy adhesives. In compression, a 17% lower failure load was measured for wall specimen with the MgO board attached to the wall frame with a 10 mm offset from the bottom plate than the wall with the sheathing flushed to the bottom plate. Under in-plane shear test, the single and two-panel composite wall systems exhibited similar shear stiffness and strength. The provision of tie-down anchor bolts increased the shear strength by almost 15% but has no significant contribution to the shear stiffness. Finally, the results confirmed the potential of this composite wall system in residential modular construction.

► Rigid polyurethane foam and Magnesium Oxide board were used for a composite wall.
► The behaviour of the composite wall is governed by the strength of the MgO board.
► Single and two-panel wall systems exhibited the same strength and stiffness.
► The tie-down anchor bolts increased the strength by 15% but not the stiffness.