Circular Cylindrical Shells under combined axial loads: an experimental study

Thin shells structures have an important role in engineering; several important examples can be found in Structural Engineering, Mechanical Engineering and Aerospace: water tanks, containment shells of nuclear power plants, concrete arch domes, piping systems, pressure vessels, aircrafts, missiles, rockets, ships. Even though many researchers have extensively studied nonlinear vibrations of cylindrical shells, experimental studies are rather limited in number; in particular, rare experimental reports have been published about shells loaded with in-plane . In this paper the response of a circular cylindrical shells subjected to axial compressive and periodic loads has been experimentally investigated. The experimental setup is explained and deeply described along with the analysis of preliminary results. The linear shell behavior is investigated by means of a finite element model in order to enhance the comprehension of experimental results in the linear field. The main goal is to investigate the nonlinear phenomena associated with a combined effect of compressive static and a periodic axial loads, the investigation have been carried out for different combinations of loads. Several interesting nonlinear phenomena have been observed such as softening-type non-linearity and non stationary response when the periodic axial load is resonant with one of the shell modes.