Numerical and experimental evaluation of the collapse resistance of MLPs under external pressure by lateral loading

This study aims at evaluating the collapse resistance of mechanically lined pipes (MLPs) by comparing results from experimental and numerical methods. Initially the mechanical properties of the pipe materials, and the friction coefficient between the layers of MLP, were characterized through lab tests. This data was then used to develop numerical simulations, which were subsequently validated by comparing them to the results of full-scale collapse tests and the DNV-ST-F101 design equation. A parametric study was performed to assess the influence of the friction coefficient and the thickness of the liner on collapse pressure. The findings indicate that the CRA liner provides significant structural reinforcement, leading to collapse pressures that exceed standard design predictions, particularly for MLPs with thick liners. Furthermore, the interfacial friction was also shown to be a contributing factor to this enhanced resistance.