Ch. 6: Reading Buildings Flashcards
To say that a building collapses without warning is a flawed statement.
The warning for structural collapse is in the ISOs ability to understand building construction and the effects of fire on the building.
What type of explicit detail and their judgment must ISOs be able to give an incident commander?
Regarding the collapse potential of a given building being attacked by fire.
What is imposed on building materials?
loads
The imposition of a load causes stress on the materials called what?
force
What is the direction or application of a load to a component?
The imposition of the load.
What are the three types of load that can be transmitted through a structural member?
Torsion, axial, and eccentric. [TEA]
How are loads applied to a structural member?
Compression, tension, and shear forces [CTS]
What characteristics do the materials used to resist load have?
load-bearing characteristics
Mass is heat resistance, and heat resistance is _______.
time
What are the four basic building material types?
Wood, steel, concrete, and masonry.
What does it lead to when steel softens, elongates, and sags when heated?
collapse
Cooling _________ _________ with fire streams is just as important as attacking the fire.
structural steel
What has excellent tensile, shear, and compressive strength?
Steel
High factory control; that is, it’s easy to change its shape, increase its strength, and manipulate it during production.
Steel
What has excellent compressive strength when cured?
concrete
A pocket of concrete that has crumbled into fine particles through exposure to heat.
spalling
What can take away the critical mass of the concrete- that is, the mass used for strength?
spalling
A lateral force that exceeds the compressive forces within a masonry wall causes its ______ ________.
quick collapse
Brick, concrete block, and stone.
Masonry
What is referred to as a combination of the four basic materials?
composite
Lumber created by gluing and pressing together sheet veneers of wood (in the same grain direction)
laminated veneer lumber (lvl)
A wood sheeting consisting of wood chips (strands oriented in multiple directions) and an emulsified glue.
oriented strand board (osb)
Rapid heading of a composite truss can cause the metal to separate from the wood.
Rapid heading of a composite truss can cause the metal to separate from the wood.
Building columns, beams, and connections used to assemble a building.
Structural elements
To predict collapse.
The ISO must constantly evaluate structural elements to determine if they can still transfer the load as designed.
Any structural component that transmits a compressive force parallel through its center is called a ________.
column
A structural element that delivers loads perpendicularly to its imposed load is called a ________.
beam
What are subject to compressive forces?
columns
What is the “weak link” in structural failure during fires?
the connection
What are the three general types of connections?
pinned, rigid, and gravity
What are a series of columns and beams used to hold up a building often referred to as?
skeletal frame or post and beam
The structural elements are of an approved noncombustible or limited combustible material with sufficient fire-resistive ratings to withstand the effect of fire and prevent its spread from story to story.
Type I: Fire Resistive
What type is typical of concrete-encased steel, monolithic-poured cement, and steel with spray-on fire protection coatings?
Type I
What type of buildings are often steel and are susceptible to steel deformation and resulting collapse?
Type II
What type are buildings made of load-bearing brick or concrete block with wood roofs and floors?
Type III
What is one of the most common uses of Type III?
Strip mall with masonry walls and lightweight steel or wood trusses.
What are common problems associated with the Type III construction?
Void spaces allowing for rapid-fire extension and collapse of lightweight structural elements.
What is used to pull back into alignment the sagging or bowing load-bearing walls?
decorative stars/ornaments (spreaders)
What type of buildings have block or brick exterior load-bearing walls and interior structural members, roofs, and floors, and arches of solid or laminated wood without concealed spaces?
Type IV
Where are heavy timber buildings mainly used for?
Warehouses, manufacturing buildings, and some older churches.
What can fire spread in a Heavy Timber building be fast due to?
Wide-open areas and content exposure.
What is the most common construction type?
Type V
What type of construction can fire enter the wall space and run straight to the attic?
Type V
Building analysis during any incident should be cyclic.
Performed on a regular basis as conditions change and time goes by.
What is the Five-Step process for predicting collapse?
1) Classifying the type of construction
2) Determining structural involvement
3) Visualizing and tracing loads
4) Evaluating time
5) Predicting and communicating the collapse potential
What are areas that are exposed to trauma, debris, and/or thrust of a collapse?
collapse zone
The failure of a roof assembly may impose weight on interior partition walls that were not designed for the load.
These become a “loaded gun,” meaning that the slightest movement could cause an explosive release and collapse.
What should be the default for all construction site fires?
Defensive operations
What is one of the important functions of an ISO?
To offer judgment about the collapse potential of buildings during incidents.
What is used for the top and bottom chord of the I beam?
Laminated veneer lumber (LVL)
Which type of connections use bolts and screws?
Pinned
What causes a rapid separating stress at the intersection
of the two materials under fire conditions when combining metal and wood to form a structural element?
Metal expands faster than the wood
Which type of buildings are most often large, multistoried
structures with multiple exits?
Type I
Which causes fire spread to be rapid in the Type IV
building?
Open spaces
What type of attack should be considered when firefighters must work within the established collapse zone area?
Flanking approach
Which is considered a fake beam due to its lightweight
materials and use of geometric shapes?
truss
How much can a 100-foot steel beam elongate at 1,000
degrees Fahrenheit?
10 inches
What accelerates the potential collapse time?
- High surface-to-mass ratio
- An imposed overload
- Higher BTU development
How thick is the EPS sheet typically?
6 to 8 inches
What is FiRP made from?
Plastic
In which step does the ISO “undress” the building when
predicting collapse?
3
What should be used to determine the structural
involvement of a fire?
Smoke and flame
What do new lightweight steel homes resemble?
Wood frame homes
At what point did builders begin to use platform framing
for wood frame buildings?
1950’s
How are connections loaded for the most part?
In shear
Which is NOT an ingredient in concrete?
Masonry
What is the correct progression in the following
assumptions?
Mass is heat resistance and heat resistance is time
Which type of load can occur in both directions?
Shear
What is used to protect structural members from fire in a
wood frame building typically?
Gypsum board
Which is NOT a common ingredient used to make mortar used in masonry walls?
gravel
How many times the height of the building should the
collapse zone be as a minimum?
1 1/2
What is the fire resistive device most often used to
protect the roof structure of the Type II building?
Dropped-in ceiling
Which type of forces are relied upon to give the masonry
wall its strength?
Compressive
In Type IV construction what is generally the minimum
dimensions of the members?
8 inches
Which has marginal tensile strength?
wood
What are Type II buildings constructed from more often
than not?
Steel
What must be used to most effectively predict building
collapse?
Knowledge base
Which type of connections use reinforced concrete and
welds to bond elements?
Rigid
What occurs to steel as it is exposed to fire?
Softens
Which type of load is imposed through the center of the
structural member?
Axial
What influences fire spread in Type II buildings?
Contents
What color smoke does unfinished wood that is being
rapidly heated emit?
Brown
Which truism about predicting collapse is correct?
The lighter the structural elements, the faster it comes
down
Where must forces be delivered for a building to be
structurally sound?
The ground
What is a structural element that delivers loads
perpendicularly to its imposed load?
Beam
What can be seen that will alert the firefighter to the
fact that a load-bearing wall has been pulled back into
alignment?
Decorative stars on the outside brick wall
Which is considered the most common type of construction?
Wood frame
What is any structural element that transmits a
compressive force parallel through its center?
Column
What is the imposition of loads on building materials
called?
Force
Which is likely to fail fastest under fire conditions?
ICF (insulated concrete forming) block
What is the first step for predicting collapse?
Classify the construction type
Which ratio determines the strength of concrete most?
Water to Portland cement
What is a series of beams placed perpendicularly to trusses to help support roof decking?
Perlin
Which type of beam spans an opening in a load-bearing
masonry wall?
Lintel
What is the extension of a wall past the roof?
Parapet wall
Which type of operation should be default at all
construction site fires?
Defensive
Which type of beam supports other beams?
Girder
Which type of load tends to pull in opposite directions on
the structural member?
Tension
What percentage of its strength does cold drawn steel lose at 800 degrees Fahrenheit?
55%
