Bending fatigue performance of L-shaped stapled one-side two-gusset-plate upholstered furniture joints in oriented strandboard

The stapled, one-side, two-gusset-plate system is a standard method for joining two structural members such as front stump and front rail in upholstery furniture frame constructions. The fatigue performances of L-shaped, stapled, one-side, two-gusset-plate joints (TGPJs) in three different oriented strandboard materials were experimentally investigated. All TGPJs were subjected to one-sided cyclic stepped bending moment regimen that is commonly used to evaluate the durability performance of upholstered furniture frames. The purpose was to determine the ratio of TGPJs’ static bending moment capacity to their corresponding passed fatigue bending moment level. It was found that the ratio averaged 2.32. Joint failure modes suggested that the resistance capacity to fatigue bending moments of TGPJs that had their final cumulative cycles to failure less than 125,000 was governed by staples’ lateral withdrawal resistance capacity in OSB materials. In contrast, staple legs' resistance to lateral cyclic load governed the resistance capacity to fatigue bending moments of TGPJs that had their final cumulative cycles to failure greater than 125,000. It is believed that this information can assist furniture engineers carrying out rational strength design of upholstered furniture frames to meet desired durability requirements.