Emergency rescue site collapse type and void formation

Most buildings are unable to withstand a variety of disasters such as tornadoes, earthquakes, floods or explosions. The extent of its destruction depends on the type of disaster and the structure of the building.
For example, steel-structured modern factories or office buildings are better able to withstand sudden violent incitement than shops or houses in the streets. Special attention must be paid to steel structures that have just experienced fire because they are more likely to collapse. However, in disasters such as major earthquakes, almost every type of building will be affected - some will completely collapse, and some buildings will have floors and walls at risk. Regardless of the degree of destruction, the same rescue techniques are used.
For the safety of themselves and others, rescue workers should master the specific patterns of building collapse. At the same time, they must prohibit untrained people from approaching the collapsed debris and rubble. Otherwise, it may cause more collapses and harm the trapped ones.

The collapse of most unconsolidated buildings can be divided into several predictable patterns. Collapsed buildings often form gaps that provide victims with temporary living space.
Rescuers should know how to locate and search for these gaps.
If the supporting structure of the ceiling, floor, or other large building components is intact and one side collapses, a so-called "a lean-to collapse" occurs.
In addition, the floor of the house is unable to afford tons of debris. Therefore, when the weight of a heavy object (such as furniture, equipment, or collapsed pits) accumulates in the center of the floor, it may cause "V-type collapse".
If the outer wall of the bearing is damaged, destroyed or collapsed outward, a large amount of debris will fall to the ground or the street. The floors, ceilings, and interior walls of buildings are collapsed into piles due to loss of support; the collapsed objects are separated only by furniture and some residual walls. This collapse is called a pancake collapse. There may be gaps between the furniture and the collapsed floor. If the support is not displaced, one can relatively safely crawl in these gaps