The results of a holistic study are presented dedicated to developing an Internet-based reliability and remaining life assessment for on-shore main pipelines with growing defects. The reliability analysis is carried out using five types of failure pressure models. Two types of limit state functions are used. The limit state functions (LSF) are comprised of nine parameters that are considered as random variables (RVs). These RVs describe the pipe and defect geometry, rate of axial and longitudinal corrosion, strength properties of the pipe wall material, operating pressure. The main reliability analysis is conducted using the Gram-Charlier-Edgeworth (GCE) method of expansion of the limit state function, which can be considered as a generalization of the FOSM and the Taylor series expansion methods, as it is capable of using arbitrary probability density functions (PDF) and takes into account the third and the fourth central moments of the non-Gaussian PDFs. Five types of PDFs are used in the analysis. The Monte Carlo simulation method was used for verifying the results obtained by the G-C-E method. The reliability of each cross-section of the pipe containing a defect is calculated, as well as the reliability of a pipeline segment or the pipeline as a whole. Sensitivity is investigated of pipeline reliability to the above nine parameters and their statistical characteristics (PDFs), which describe pipeline and defect geometry, corrosion rates, pipe wall material properties and operation mode. The expected number and volume of repairs are calculated using some values for the ultimate permissible pipeline failure probability. Comparative study on the computer time needed for calculation of reliability by the G-C-E and the M-C methods is conducted in relation to their applicability for remote Internet usage. A brief description is given of the Internet-based software that implements the described above technology.

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