Multi-fidelity approach for uncertainty quantification of buried pipeline response undergoing fault rupture displacements in sand

Abstract

Listen

Translate article

A new efficient approach for uncertainty quantification of pipeline structural response undergoing reverse-slip fault rupture displacements in sand is presented using multi-fidelity Gaussian processes. Uncertainty quantification problems generally take large numbers of scenarios to be analysed considering variations in the influencing parameters. Analysing large numbers of computationally expensive detailed geo-technical numerical models is practically not feasible. Hence, a multi-fidelity approach employing Gaussian process is proposed to tackle this problem which combines the accuracy of a relatively few number of detailed geo-technical numerical models and the efficiency of large numbers of simplified numerical models to track the uncertainty response. The detailed model utilizes a previously validated pipe-soil finite element (FE) model including a non-linear sand constitutive model implemented in finite element software ABAQUS. The simplified model utilizes beam element pipe and bi-linear soil springs. The multi-fidelity model is first trained using data from high-fidelity and low-fidelity model analyses, thereafter cross-validated and subsequently used to quantify uncertainty in the peak compressive strains generated and to identify the most sensitive input variables. Finally, fragility curves are derived for a site specific pipe-soil fault rupture problem.