For the blasting and demolition project of a 130 m multi-tube sleeve chimney, the LS-DYNA finite element software was used to simulate the blasting incision by unit failure using a separated common-node model. The collapse process of the multi-tube sleeve chimney was numerically simulated, analyzed and compared with the actual blasting effect. The results show that the effective stress is mainly concentrated on the edge of the remaining part of the support when the blasting notch is forming. However, the notch closure stage of the falling speed is different due to the length and slenderness ratio and the nature of the material of the outer chimney and the inner sleeve are different. The simulation shows that the external chimney and the steel inner tube would be collisional at the notch closure stage as the internal and external detonation simultaneously. Choosing the detonation method with a delay of two seconds between internal and external components will achieve the ideal collapse effect.