GFRP面板-冷弯薄壁型钢组合梁受弯性能试验研究

Traditional composite sandwich structures used in civil engineering applications mainly use lightweight and low modulus materials as core material, which results in ultimate strength being controlled by the stiffness of the cross-section rather than by strength of material, i.e., the strength of the FRP material is not fully mobilized. A glass fiber reinforced polymer (GFRP) composite laminates-cold formed steel composite sandwich beam (GCS beam) with properties of light weight, high strength was proposed. The GCS beam composed of GFRP skins, light-weight polyurethane (PU) foam core and cold formed steel (profiled steel sheet), where the GFRP skins and the profiled steel sheet was enhanced by stainless steel core rivets. Four point bending tests were carried out to explore the flexural behavior of the GCS beams, and analyse the effect of parameters of open direction of the profiled steel sheet and the interface enhancement on the failure modes, bending stiffness, ultimate bending strength and ductility properties of the novel sandwich beams. Test results show that GCS beams have a better serviceability limit state and ultimate limit state load bearing capacity, which are increased by 306.2% and 157.5% compared to the conventional sandwich beam, respectively. The stainless steel core rivets, used as interface enhancement, can restrain the interface crack propagation effectively and improve the deformability of GCS beams remarkably. The whole work can be taken as a reference for manufacture, design and application of this kind of structural members.