UHPC-XPS insulation composite board reinforced by glass fiber mesh: Effect of structural design on the heat transfer, mechanical properties and impact resistance

Extruded foamed polystyrene (XPS) and ultra-high performance concrete (UHPC) are the ideal insulation and structural materials for preparing sandwich composite boards, respectively. However, how to design the multilayer structure of composite board to maximize thermal insulation, mechanical properties and impact resistance has not been clarified yet. In this study, styrene-acrylic emulsion was coated on the surface of XPS to improve its wettability, and glass fiber mesh-reinforced bonding mortar with vac-ethylene copolymer emulsion was used to improve the adhesive properties between UHPC and XPS layers. Then the contribution of each layer in heat-transfer, load-bearing, and impact resistance were investigated and simulated by finite element analysis. By separating XPS and UHPC into serval layers, the midspan displacement at peak load and fracture energy of composite boards increased by 689.4% and 39.1% respectively, then roles of each layer in composite board were discussed. The results provide an effective method to prepare high performance composite board by multilayer structural design, and then promote energy-saving and emission-reduction of prefabricated wall system and even building industrialization.