Card Set Information
tags " Chapter 6 and 7"
Buildings must be built to resist the forces of
Wind, snow, rain, and gravity
Wind, snow, rain, and gravity create ___.
Loads are imposed on
(Loads) This imposition causes ____ on materials-called ___
The direction or application of a load to a component is the ___ of the load
___ types of loads can be transmitted through a structural member. They are:
Axial(compression), eccentric(tension), torsion(shear) can occir in both directions
Loads are applied to a structural member as :
Advanced material technologies have found there way into structural elements. Buildings are being assembled using :
Plastics, graghites, wood derivatives, and other composites
4 basic material types:
Wood, steal, concrete, and masonary
Wood has ___ resistance to forces compared to it's weight, but does the job for most
residential, and small comercial buildings
Steal is a mixture of __ and __ into structural shapes to form elements for buildings
Carbon and iron ore heated and rolled
Steal has excellent__ strengths
Tensile, shear, and compressive
Steal is a popular choice for:
Girders, lintels, cantilevered beams, and columns.
Steel has __ ; that it is easy to ___
High factory control
Change its shape, increase its strength, and manipulate during production
The specific range of temperature that at which steel loses it's strength depends on :
How it was manufactured
Cold drawn steel, like ___, loses _% of it's strength at _
55% -- 800° F
Extruded steel used for __ lose __% of it's strength at __
At __ a 100' long beam can elongate __
Steel __ when heated
Softens, elogates, and sags
Concrete is a mixture of:
Portland cement, sand, gravel, and water
Concrete has excellent __ strength when __
The curing process creates __ that bonds the mixture to achieve __
A chemical reaction
The final strength of concrete depends on:
Ratio of materials especially water to portland cement
Concrete has poor:
Tesile and shear strength
Reinforcing steal that becomes exposed to a fire can transmit heat within the concrete, causing :
Catastropic spalling and failure of the structral element
A __ force that exceeds the __ forces within a masonry wall cause:
Its quik collapse
of particular interest are the many __ that are widely used for structural elements
Emulsified glue :
The OSB and LVL I- beam is ___ a solid wood joist. It __ when heated.
FiRP can be mixed with wood to give it __ with __
incredible tensile strength
Structural elements, defined simply as:
Columns, beams, and connections used to assemble a building
To predict collapse the iso must ___ structural elements to determine___
If they can still transfer the load as desiged
Beams are used to create a___. Beams are subjected to the imposed load of____.
Itself and anything placed on it
Spans an opening in a load-bearing masonary wall, such as over a garage door opening (often called a header)
Supports other beams
__-"Fake" beam because it __.
Uses geometric shapes, light weight materials, and assembly components to transfer loads just like a beam.
Types of connections
Pined, ridgid, gravity
The general classification of construction methods helps the fire officer understand the __.
Materials, methods, and components present in a structure
Type II construction
Structural elements do not qualify for type I construction
Has many void spaces which fire can spread undetected
Fires can spread from store to store through wall openings and shared ceiling and roof-support spaces
Common problems associated with this type of construction are void spaces allowing for rapid fire extension and collapse of lightweight structural elements.
Type III ordinary
A masonry wall requires __ from __ to make it sound.
In the early 19_'s, builders started using ___ framing
__ become a significant collapse threat, especially in newer buildings.
Fire and heat that penetrate wall, floor, or attic spaces
The biggest collapse threat to new lightweight steel homes is___- expect __, and
Fire in an unfinnished basement
General collapse of flooring into the basement.
lightweight steel homes:
__ will likely sag before collapse as it is __ and uses __ to help add rigidity
ICF buildings use ___ to form a concrete mold for walls.
(EPS) Expanded polystyrene
concrete is poured into small cylinder cavities to give:
The wall compresive strength for the roof
A construction method that uses panels made from OSB and EPS for load bearing walls and roofs
SIP-walls are typically __ thick
Failure of the wall panel causes instability in the roof structure.
Expect rapid structural failure of these buildings during fires
If the building does not fit a classic type or is of multiple types, simply call it
Determining whether a fire is a contents or structure fire is
5 step process for predicting collapse?
1. Classify the construction type
2. Determine structural envolement
3. Visualize and tra e loads
4. Evaluate time
5. Predict and communicate collapse potetial
Dark gray or black smoke venting under pressure from structural seams, ridge boards, eaves, and attic vents is a indicator...
That heat and likely fire are present in that space.
This step in the 5 step process for predicting collapse is more an art form
Step 3 visualizing and tracing loads
Weak links that lead to collapse (7)
Connections, overloading, occupancy switch, trusses, void spaces, stairs, parapet walls
Each type of building construction has it's own weak link; this is why __ are so valuable.
Study of building construction text and site visits
In some cases the connection relies on __ to hold it in place ; a ___ may cause the connection to fail
Gravity and an axel load
Shift or lateral load
Excessive __ loads place stress on building components, which are vulnerable to early collapse when__
Live and dead
attacked by fire
__ usually hold together trusses
Trusses are used in
Roof, floor, and mezzanine assemblies
Voids are numerous in type...
Type III ordinary construction
Parapets are typically made of...
A collapse zone consists of the areas that are exposed to
Trauma, debris, and/or thrust should a building or part of a building collapse
With new truss systems, interior floors can ___, yet the walls and roof remain -____.
Collapse into the basement
A general collapse
Observations that make collapse likelihood obvious:
1. DETERIORATION OF MORTOR JOINTS AND MASONRY
2. SIGNS OF BUILDING REPAIR (SPREADERS)
3. BULGES AND BOWING WALLS
4. SAGGING FLOORS
5. ABANDONED BUILDINGS
6. LARGE VOLUME OF FIRE IMPINGING ON STRUCTURE
7. MULTIPLE FIRE IN THE SAME BUILDING, OR PREVIOUS FIRE DAMAGE
The best approach for firefighters when responding to fires in buildings under construction is to...
SMOKE CAN BE BEST DEFINED AS
THE PRODUCT OF INCOMPLETE COMBUSTION THAT INCLUDES AN AGGREGATE OF SOLIDS, AEROSOLS, AND FIRE GASES THAT ARE TOXIC, FLAMMABLE, AND VOLATILE
Flashpoint, self-ignition temp and flammable range in air
-15° 450° 3-31%
12° 928° 1-8%
0° 1,000° 12-74%
CO is __ and doesnt have a __ the flammable range of CO is __ at it's ignition temp. Below __ the flammable range of CO is ___
Considered a gas only
Acrolein is a by-product of the I'm complete combustion
Wood, wood products, and other cellulosic materials.
__ can also render Acrolein
Most ___ release benzene while burning
__is a common product of the burning of fuel oils
HCN is produced when
High temperatures break down nitrogen-containg products
Is quit flammable and is considered toxic
Hydrogen cyanide (HCN)
___ extremely flammable and ultimately dictates fire behavior in a building
Warning signs of flashover :
Turbulent smoke flow
Warning sign of backdraft
Bowing, black stained windows
Signs of extreme heat on outside of box
Warning signs of smoke explosion
Smoke trapped above the fire
Smoke starting to pressurize
Warnig signs of rapid fire spread
Increase in smoke speed
Smoke flowing from hallways and stairways faster than a firefighter can move
Carbon monoxide is ignitable with a spark or flame at but has a
Small flammable range
As CO heats up
Its flammable range widens
Only two things can cause smoke to pressurize...
Heat and smoke volume
Turbulent smoke flow is caused by:
The rapid molecular expasion of the gases in the smoke and the restriction of this expasion of the box
Fast moving white smoke indicates
Smoke you see has traveled some distance
White smoke that is slow or lazy
Indicative of early stage heating
Black fire sure sign of
Impending autoignition and flashover
If the building is sprinkled, then the Presents of low lying smoke can indicate that the
fire is not controlled by the system
A hot humid day should find the smoke Climbing straight up into the atmosphere; yet you see that the smoke is coming out and laying down. This indicates that the smoke
has been cooled, either by distance or by a sprinkler system
Most buildings do not allow fires to maintain...
Thermal balance is the notion that heated smoke rises and in doing so creates
A draft of cool air into the flame (heat) source.
Light, thin smoke showing from more than one opening of a very large building is a
By watching smoke outside a building the ISO can determine
The effectiveness of the firefight
PPV as a fire attack tactic is contradicted if
Smoke is turbulent
Location of fire seat is unknown
Fire suspected to be in a vented, combustable void space.
Once you ___ your ability to read smoke
Capture the basics and start practicing them
improves exponentially and you can read smoke in seconds
Reading smoke 3 step process step 1
View the 4 attributes compare differences from each opening should give an understanding of size, location, and spread potential and allows capture of hostile fire event
Reading smoke 3 step process step 2
analyze contributing factors see if they are affecting 4 attributes. This step should refine and/or confirm your read
Reading smoke 3 step process step 3
Determine rate of change
If the rate of attribute deterioration can be measured in seconds, it is likely that fire fighters are at risk
Remodeled buildings should always evoke a concern of