Numerical analysis of the behaviour of gas pipes buried into sand

In daily life, society needs to obtain usable energy at the lowest possible cost. Natural gas is one of the main energy sources with oil and coal. Natural gas is a gas mixture composed almost entirely of methane to which very small amounts of other gases are added, and is used daily in many households. It has many uses and this type of energy source has many advantages. One of these advantages is transportation, because gas is easily transported through underground pipelines and can be used for various purposes. This research project is dedicated to understanding the impact of surface loads on underground pipes buried into sand, using finite element models. These models study the issues through several aspects: first, consider a complex soil model to simulate soil/structure interactions that are more faithful to the real sand behavior. Three main analyses were performed. The first analysis consists in modelling the problem on a small and large scale in order to obtain, once normalised, comparable results. The second type of analysis involves studying the behavior of small-scale models during loading and unloading cycles to highlight the effects of nonlinear soil behavior. Ultimately, the influence of pipe thickness on the overall behavior of the soil/pipe structure was studied. Performing this numerical analysis is to support future experimental activities. The experimental campaign will include small-scale laboratory tests in a sand tank equipped with strain gauges and miniaturised stress transducers.