What term is used for a collapse that occurs after the initial collapse?

The term "secondary collapse" specifically refers to a collapse that occurs after the original or initial collapse of a structure. In the context of firefighting and rescue operations, understanding secondary collapses is crucial because they represent a significant hazard to both firefighters and potential victims. When a building experiences an initial collapse, the structural integrity of the remaining elements can be compromised, leading to further failures as loads are redistributed or if certain structural components fail due to stress or damage.

Recognizing the signs of a possible secondary collapse enables firefighters to assess risk effectively and develop strategies to protect themselves and those they may be trying to rescue. The dynamics involved in a secondary collapse can vary widely depending on the building's design, the materials used, and the nature of the initial collapse.

Other terms in the choices might describe general failure of structures or situations related to abnormal collapses, but they do not specifically capture the nature of a collapse following an initial one as clearly as "secondary collapse" does. This precision is important for ensuring safety and effectiveness in emergency situations.