ABSTRACT:
To enable the connection between structural members, coping is provided to avoid interference between the connected members. While the fabrication of steel beams in offshore structures are common, the presence of copes increases the risk of a local failure. Coped beams need to overcome certain special issues, namely bending and torsional stiffness, local web buckling near the top coping edge, and reduced torsional rigidity. Due to geometric discontinuity, a high-stress concentration near the cope corner could cause the local buckling after initial yielding. As the top flange provides no restraint, block shear failure is one of the common types of failure in the bolted and welded connections of the coped beams. Under impact loads that occur on the offshore topside, there exists a possibility of developing fatigue cracks in the coped region due to induced cyclic compressive stress in the presence of tensile residual stress. A shear block failure is also expected under high concentrations of dynamic loads arising from drilling stock and production equipment. Large-span coped beams showed lateral torsional buckling, transfer of excessive moment, and shear stresses to the connections. Coping facilitates the housing of pipelines, HVAC conduits, and electrical & telecommunication lines, which shall be easily accessible from the shop floor. offshore platforms are vulnerable to unintentional loads, such as high-velocity impact from falling objects. A conventional steel offshore platform's structural components are incapable of withstanding enormous stresses and deformations caused by accidental loads. To address this issue, functionally graded materials with high pressure and temperature resistance are being developed for offshore platform applications. Recent research on coped beams with rounded corners showed a significant influence on the failure modes and buckling processes of single-coped beams. Particularly for a single-coped beam with a deep coped depth, the application of rounded corners significantly increased energy dissipation and load-carrying capacity. The proposed research is set to investigate experimentally and numerically the response of coped beams with steel and functionally graded material (FGM) under monotonic load. Further, it aims to study the impact resistance of coped beams with steel and FGM under drop object test, damaged and free conditions, and blast loads. The proposed research is novel as the coped beam with FGM plates are proposed to increase the strength, corrosive, and impact resistance. It further facilitates offshore topside to carry pipelines, telecommunication cables, electrical wires, and HVAC conduits.