With the development of nuclear power plants, more and more super-large cooling towers will be built in China. For the safe operation of nuclear power plants, people begin to pay attention to the causes which lead to collapse of cooling towers, collapse modes and the secondary disasters caused by the collapse of cooling towers. However, the current knowledge to predict the collapse modes and the ground vibration induced by the collapse of cooling towers subjected to the accidental loads are not enough. This paper concerned the causes, process and mechanic behavior of the collapse of a cooling tower. Meanwhile, the prediction of the ground vibration due to the collapse of the cooling tower was completed in a parallel project. Using dynamic finite element program LS-DYNA, a 3D finite element model for a super-large cooling tower was developed and the nonlinear material models were used. In this paper, four categories of accidental loads were considered to cause the collapse or local failure of the tower, e.g., the vehicle collision, the local explosion, the uneven settlements of the foundation and the missile attack. It was found that the loads of the vehicle collision, the missile attack and small TNT equivalent (lighter than 2000kg) explosives might result in the local failure of the cooling tower but the tower could still keep stable; the uneven settlements of the foundation might cause the collapse of the cooling tower , but the collapse modes would be different according to the affected area and the values of the uneven settlements which were simulated by demolishing different columns at the bottom of the tower.
展开▼
