A Study of Counter-intuitive Behaviors of Pin-ended Thin Spherical Shell Subjected to Rectangle Impulse Loadings

The counter-intuitive behaviors of pin-ended thin spherical shell subjected to short rectangle impulse loadings are investigated with ANSYS/LS-DYNA.On the basis of the study of their displacement-time history curves,final deformed shapes,energy relationships and sensitive characteristic of its occurrence,the occurrence mechanism of the counter-intuitive behaviors is discussed.The results show that the counter-intuitive behaviors of thin spherical shell is similar to those of the thin circular plate,while their final deformed shapes are more complicated than that of the thin circular plate's.Their counter-intuitive behaviors occur only when the applied load amplitudes lie in several narrow and proper load ranges;Corresponding to the occurring of the counter-intuitive behaviors,the number of the rebounding of the shells' deformation decreases from a few times to zero with the increase of the load amplitude,and the occurrence of their counter-intuitive behaviors have sensitive characteristic to the micro change of the load.When the counter-intuitive behaviors occur,the ratio of the strain energy and the kinetic energy reach a proper range;the counter-intuitive behaviors of the spherical shell have the similar characteristic to its dynamic buckling.