Failure Modes And Ultimate Strength Of Tubular Joints Under Elevated Temperatures

Fire presents one of the most severe design conditions for offshore steel structures since unlimited supply of fuel and oxygen may result in rapid growth and spread of fire on the structure. As one of the major components of the oil rig, the design of tubular joint always requires careful attention for extreme condition. Extensive investigations, including testing, numerical models and theoretical models have been conducted on the behavior of off-shore tubular joints. However, there is no such publication for tubular joints under fire conditions. In this study, the ultimate strength of CHS tubular T-joint under elevated temperature was investigated. Finite element models (FEM) of the tubular T-joints were constructed. Available test data were used to validate the FEM models at ambient temperature. The validated models were then used to investigate the ultimate strengths of joints under elevated temperature by implementing material model recommended by Eurocode 3. Based on this study, failure modes and ultimate strengths of tubular joints were obtained. In addition, influences of a few dominant dimensionless parameters, loading types at various elevated temperature were studied numerically.