What are two types of structural collapse patterns?

The identification of structural collapse patterns is essential in rescue operations as it helps rescuers anticipate potential hazards when working in or around collapsed structures.

Focusing on the first option, pancake collapse is a pattern where floors fall onto each other in a stacked manner, resembling a stack of pancakes. This type of collapse can create voids between the floors that may be occupied by trapped victims, complicating rescue efforts. Leaning collapse refers to a scenario where a structure loses its vertical stability and leans at an angle, which poses an additional risk of further collapse and can trap individuals on one side of the structure.

Understanding these patterns allows rescue technicians to assess the situation more accurately, plan their operations on stable surfaces, and implement safety measures effectively. The knowledge of pancake and leaning collapses is crucial for both hazard assessment and developing strategies for victim recovery.

Other collapse patterns, such as those mentioned in the other choices, may indeed occur under different circumstances but do not adequately capture the fundamental types of structural failures that are frequently experienced in building collapses. For instance, while partial and complete collapse describes the extent of the structural failure, they do not classify the patterns in which the collapses manifest. Therefore, pancake and leaning collapse provide a more specific understanding needed in emergency