This work focuses on a development of a finite element model that simulates corrosion phenomenon and its influence on structure rupture (pipelines). Subsequently, the pitting effect on reliability and pipelines lifetime is studied. In this paper, the investigated structure material is characterized experimentally, in order to determine the maximum strength and stress resistance. Therefore, a numerical model was developed under ANSYS code to simulate different loads to obtain the stress concentration factor as the stresses could surpass the yielding limit in the corrosion impact, and to determine the Von Mises stress. A corrosion model and residual stresses used in the literature are coupled with the probabilistic model to find the limit state function. Thus, failure probability and structure reliability index under the effect of pitting corrosion phenomena are calculated and the obtained results are discussed and analyzed.

The corrosion inhibition of nickel in 0.5 M H 2 SO 4 by cysteine was investigated with various electrochemical methods and surface observations by SEM. The cyclic voltammetry revealed that the current density is the highest in absence of the cysteine and decreases with increasing inhibitor concentration. The cysteine is an anodic inhibitor. The polarization and electrochemical impedance spectroscopy showed that the cysteine has a poor inhibitive effect. The surface observation by scanning electron microscope corroborates the addition of cysteine has no significant improvement of the surface morphology of nickel electrode in 0.5 M H 2 SO 4. Results obtained by different methods corroborate each other.

A suitable piezoelectric accelerometer mathematical model is proposed to extract a relationship of motion relative frequency as a function of natural frequency. This relationship helps to select appropriate accelerometer frequency range that minimizes measurement error and improves accuracy. It also allows deducing a formula relating the damping rate and the measurement error of the accelerometer. To protect the accelerometer from failure, the resonance phenomenon effect must be minimized. In order to achieve this objective, physical principle is modeled to find a precise relationship which can determine the accelerometer appropriate frequency range. The developed model was simulated and the obtained results have showed that the selection of the frequency range has minimized the measurement error, increased the accelerometer accuracy, and reduced the resonance effect. Finally a comparative study was conducted to show the importance of the obtained results compared to recent literatures.