Abstract: It is generally known that chimney might break at a certain place before it hit the ground during a demolition blasting. However，previous models have assumed that the mass distribution of the chimney is uniform. The chimney model analyzed in this paper is a more realistic one with non-uniform mass distribution.By seeking the maximum point of the torque，the possible rupture point of the chimney is given.

Key words: chimney, fixed-axis rotation, rupture