Collapsed structures Flashcards
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Collapsed Structures
Causes of collapse can be broken down under two main headings, What are they ?
Natural or Human
Collapsed Structures
What are the causes of natural collapse?
- earthquake
- hurricane
- lightning
- flooding
- subsidence (see pic)
- accidental gas explosion
Collapsed Structures
What are the causes of human collapse ?
- premises under renovation
- accidental impact (see pic)
- arson
- terrorist induced (aeroplane impact, vehicle impact. etc).
Collapsed Structures
There are 3 type of collapse, what are they?
- Internal collapse
- External collapse
- Total collapse
Collapsed Structures
What are the 4 types of internal collapse?
- Pancake collapse
- Lean-to collapse (see pic)
- “V” collapse
- Tent collapse
Collapsed Structures
What are the 3 types of external collapse?
- 90o angle collapse (see pic)
- Curtain fall collapse
- Inward/outward collapse:
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What does total collapse mean?
This is the most severe form of structural failure, where all the floors have collapsed to the ground or basement level and all walls have collapsed onto the floors.
Collapsed Structures
Rescues from collapsed structures, there is a heightened risk of injury to personnel resulting from?
- Obstructed or restricted access
- Restricted vision e.g. smoke, dust
- Underfoot conditions
- Falling objects
- Overhanging hazards
- Airborne particulate
- Oxygen deficient atmospheres
- Secondary collapse
- Weight and position of casualties
- Bulk and weight of debris
- Explosive/flammable atmospheres
- Poor lighting
- Biological hazards
- Exposed and damaged utilities, (gas, electricity and water)
- Asbestos
- Sharp and protruding objects
- Further acts of terrorism where this may have been the cause
Collapsed Structures
What measures to be considered at collapsed structures?
- Appliances and equipment may cause vibration and further collapse
- Appropriate level of PPE (e.g. BA, GTCPS). Establishment of restricted zones
- Doors or windows should not be forced as they may be wedged in a position that is supporting a load
- When inside buildings keep close to walls if the floor is weakened
- Maintaining liaison with, and control of, specialist contractors and the activities of other rescue personnel.
- Utilities should be isolated,
Collapsed Structures
What specialist equipment is available within the Brigade?
- Thermal Image Camera [TIC]
- Search Camera
- Delsar listening device (see pic)
- Snake eye search camera
- Con-space
Collapsed Structures
What are the six stages of rescue?
(R.E.P.E.A.T)
- Reconnaissance and survey
- Elimination of utilities
- Primary surface search and rescue
- Exploration of voids and spaces
- Access by selected debris removal
- Terminate by general debris removal
Collapsed Structures
What type of collapse is this?
Pancake collapse
Pancake collapse is often mistakenly referred to as total collapse. This type of collapse occurs when there is a failure of load bearing walls, or an upper floor fails. The floor falls horizontally, or pancakes upon a lower floor and the added weight causes this and other floors to fall to a lower level, but not always to ground level
Collapsed Structures
What type of collapse is this?
Lean-to collapse
Lean-to collapse occurs when one of the supporting walls collapse and a beam fails at one end. A triangle shaped void is formed where occupants may survive
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What type of collapse is this?
‘V’ collapse - occurs when heavy loads or a collapse from above, place undue strain on the centre of the floor, which causes it to fail in the middle
Collapsed Structures
What type of collapse is this?
Tent collapse - occurs when floor beams fail near the outer walls, but an interior load bearing wall or girder remains intact
Collapsed Structures
What type of collapse is this?
9Oo angle - collapse is the most dangerous form of external collapse as the wall falls outwards for a distance at least equal to its height
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What type of collapse is this?
Curtain fall collapse - is where part of the wall comes straight down and debris piles up near the base
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What type of collapse is this?
Inward/outward collapse - is where the wall cracks horizontally in the middle and causes the top half to usually fall inwards and the lower half to fall outwards
