According to the basic principle of the experimental modal analysis

the strain modal of the vertical steel crude oil storage tank model with doom roof were tested.The ability of identifying the damage degree and location of the crude oil tank model using modal parameters were observed.Experimental analysis shows that the more damage of the tank body exists in the same location

the higher frequency is reduced

but the changing regulation of the relative changing rate of the natural frequency is not pronounced.The train modal shape cannot give information on the damage location

but the curves of modal shape difference can be used to identify the damage location.The frequencies tend to decrease as the liquid height inside the model tank rises

which reflects the effect of the additional mass and additional damping.It is also shown that capacity of liquid inside the model tank does not have much effect on the identification of the damage location.