Fatigue life predictions based on fracture mechanics calculations are required to satisfy an increasing level of safety demanded by industry. These predictions are mainly used to schedule NDT inspections and with inspection data make structural integrity assessments. The periodic inspection-assessment process can lead to the implementation of a fatigue crack repair by crack removal. Fracture mechanics analysis is used again to determine whether or not a repair will be effective. For the case of tubular joints, in offshore structures, once repairs have been shown to be ineffective it is usually required to install a clamp to maintain the continuity of joint members if the structure is still required for production. In this paper a fracture mechanics analysis of crack repaired joints based on Y factors is presented. The analysis is used to predict fatigue life after crack removal and is validated against T-butts experimental data. The analysis is also extrapolated for the prediction of fatigue life of crack repaired tubular joints.

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Recientemente se ha demostrado que la recuperación de la función de Green puede realizarse a partir de ruido sísmico. Esta función es la característica fundamental del medio donde se propagan las ondas sísmicas. En este trabajo se plantea una formulación –para el caso 2D- que permite la recuperación de la función de Green a partir de ruido sísmico. Se estudian varios tipos de medios homogéneos caracterizados por sus velocidades de propagación y relación de Poisson. Adicionalmente, para el caso bidimensional, donde se propagan solamente las ondas P y SV, se discuten y comprueban las contribuciones de energía de correspondiente a cada tipo de onda sísmica.