Dust release and tensile strength of the non-volatile layer of cometary nuclei

► The hierarchic structure of the dust aggregates reduces the tensile strength of the crust. ► The existence of a dust crust leads to an increase in ice-surface gas pressure. ► The pressure of pure water ice is not sufficient to destroy the dust crust. ► The pressure of pure carbon dioxide ice can destroy the crust even at R > 1 AU. ► The formation and destruction sequence of the dust crust can be repetitive.