Investigation of Composites-Metal Joints in Repaired Oil Storage Tanks

The finite element analysis has been used to assess composites-metal joints in repairing of corroded oil storage tanks. Abaqus software was used to simulate the oil tank storage under hydrostatic loading. The intralaminar damage was detected on each layers of laminated composites using the Tsai-Wu failure criterion. In addition, a thin layer of adhesive with perfect bonding was modeled between the metal and laminated composites. Numerical results showed that due to stress concentration, the most probable location of intralaminar damages in composite laminates was near to the location of the bottom and wall of the tank. In order to overcome this problem, polymeric fillet was used to decrease stress concentration in this region. Following FE analysis, the effects of different geometrical defects on normal and shear stress distributions of the adhesive joint were investigated. These defects were simulated using a circular hole with the largest size of the defect in a real case, at the bottom of the oil tank in a radial distance from the wall. The obtained stacking sequence of laminated composites were used to repair several oil storage tanks and confirmed the simulation results.