Experimental study on the mechanical behavior of buried pipelines subjected to thermal load cycles

This paper presents an experimental study on the mechanical behavior of buried pipes subjected to thermal load cycles. Firstly, stresses and deformations are measured experimentally on a buried pipe subjected to monotonic and cyclic thermal loads, hence reproducing the typical operating conditions of buried piping systems. Subsequently, a numerical model is developed using the finite element method, which is validated using the results obtained experimentally. Subsequently, this computational model was used to carry out a parametric study of the influence of the mechanical properties of the soil on the stress state of the system. Finally, from the results obtained experimentally and numerically, it is concluded that the most critical situation in terms of stresses takes place when the pipe is firstly placed into operation, i.e. in the first cycle of thermal load and the other variables studied have little impact.