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Flashcards in Building Construction/Collapse Deck (53)
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1
Q

Why study building construction?

A
  • Understanding of fire spread
  • Understanding of collapse potential
  • Understanding of hidden dangers
  • Understanding of how to apply strategy and tactics to fight fire safety based on building construction specifics.
  • Because building on fire are our work place and it is in our best interest to understand the hazards and characteristics of our workplace.
2
Q

Who said “A building does not drop from the sky as does a disabled aircraft. Neither is it a transient, much as a ship, a truck, or a train. Very often it has been in existence since long before any of the firefighters at the scene where born. Yet sad to say, in many cases the building might as well be a spaceship from Mars for all the Fire Department knows about it.” ?

A

Francis Brannigan

3
Q

Average lifespan of a building is ____

A

75-100 years.

24hr/day gravity is trying to pull it down.

4
Q

Again, why do we study building construction?

A
  • On average, 110 firefighters still lose their lives each year!
  • Since 1900’s, the frequency of fires has dropped considerably.
  • Since 1900’s, the frequency of firefighter deaths has stayed the same.
5
Q

Building construction language

A

a. It is important for us to be able to speak the right language in regard to building construction
b. Enables us to communicate with other agencies
c. Enable s us to be more specific when speaking to each other
d. Helps our professional image
e. Clear, precise communication is essential on the fireground!

6
Q

Forces placed upon structural components are known as ____

A

loads.

7
Q

All firefighters should know what about loads?

A

i. Have a basic understanding of loads within a building.

ii. Be able to understand how the building loads will change when the building is compromised.

8
Q

What is a GRS and what does it do?

A

Gravity Resistance System

i. All structural elements and connections that support a transfer loads placed on a structure are part of GRS
ii. Designed to transfer all loads placed on the structure down to the ground.
iii. Compromise of GRS interrupts load transfer to ground. Thus loads are placed on adjoining structural members that were not meant to handle them.

9
Q

What are the two types of loads caused by gravity?

A

Dead loads

Live loads

10
Q

Whats a dead load?

A

weight of the building and everything permanently attached to it

a. We care about dead loads because added dead loads such as AC units may not have been planned for structurally.
b. Materials are expensive.
i. Reduction in dead weight at the top of a building allows reductions in the overall weight of GRS.
ii. Less mass in structural members = less fire resistance, as fire resistance is a function of its surface to mass ratio

11
Q

What are orthostatic vital signs?

A

Orthostatic vital signs are a series of vital signs of a patient taken while the patient is supine, then repeated sitting up, then again while standing. A variation is to check blood pressure and heart rate in supine and then standing positions only. The results are only meaningful if performed in the correct order (starting with supine position)[1][2][3] Used to identify orthostatic hypotension,[4] orthostatic vital signs are commonly taken in triage medicine when a patient presents with vomiting, diarrhea or abdominal pain; with fever; with bleeding; or with syncope, dizziness or weakness.

12
Q

What is a live load?

A

the weight of all movable things in and on the building, such as people, furniture, and supplies.

a. We care about live loads because they cannot be specifically calculated ( must be estimated based on building use)
b. Building codes specify minimum designs for specific uses.
i. Uniform Live load for distributed loads
ii. Concentrated load for specific large objects.
c. If the building changes, the actual live loads may change, but unless it’s renovated, the structure was designed for a different live load.
d. Firefighting can add live load to the structure that it is not designed for. For example, a 1000GPM master stream will at over 8000lbs a minute…

13
Q

What are some other things about loads that would be handy to know?

A

i. Loads placed on a building create stress within the materials bearing the load.
ii. How and where the force or load is applied to the materials determines what internal stresses the material experience.

14
Q

3 types of stress in a material

A
  1. Compression: squeezing things together
  2. Tension: pulling things apart
  3. Shearing: sliding or bending type stress in the member.
15
Q

Define Axial load

A
  1. Loads applied parallel to the axis of the member and pass through the centroid of the cross section of the member
  2. Compressive
  3. Tensile
16
Q

Define Tension (Flexural or Bending stress)

A
  1. Force applied perpendicular to the axis of the member

2. Compressions on the top by the applied load and tension on the bottom.

17
Q

Define Eccentric Loads

A
  1. Loads that are applied parallel to the axis of the member but that do not pass through the center of the cross section of the member.
  2. Causes compression on parts underneath the load and tension elsewhere.
18
Q

Define Deformation

A
  1. Different materials react differently to different forces. Duh.
    a. Concrete is good under compressive loads but not tension
    b. Steel is good in both tension and compression depending on its makeup
    c. Wood is decent in compression as well as tension.
  2. Deformation is the change in size and shape of member under a load.
19
Q

Define Elasticity

A

a. The ability of a material to return to size and shape after deformation under load
b. A ductile material can be subject to a large amount of stress without breaking
c. A brittle material will break early when subject to a large amount of stress.

20
Q

What’s an environmental load?

A

i. Based on where a building is built, it must be able to withstand different types of environmental loads
1. Snow, wind, earthquakes, hurricanes, tornadoes, etc.
ii. Calculating snow/rain loads
1. Can be distributed or concentrated
2. Calculated based on average snowfall levels for the area (using a worst case scenario)
3. Normal live load calculation is 20psf for roofs (FF ~225psf-275psf)
4. Rain load obviously depends on if the water is able to run off or not and how quickly.

21
Q

What do we know about structural stability?

A

a. Depends on the loads placed on the building
i. Designed vs undersigned
ii. Dead/live loads
b. Also important is the method of load transfer
c. Buildings are meant to transfer all loads through the structure to the ground.
d. Methods of connection of its members are an important component.
e. Consider the connection of the floors to the building…
f. A building can be built with super strong materials, but if they are not connected in a way that is as strong as the materials themselves, it will fail when subjected to extraordinary loads.
g. A building is only as strong as its connections!!!

22
Q

What is fire loading?

A

i. How well does a building withstand fire?
ii. As we build with more engineered materials, to reduce the weight and amount of materials used, what happens to surface to mass ratio?
iii. As the surface to mass ratio increases, the fire resistance of the structure decreases.

23
Q

What is load application?

A

a. Distributed loads: loads distributed over a large area
b. Concentrated: loads applied in a small area (point loading)
c. Impact load: a load applied while at motion
d. Static load: A load that is applied slowly and remains nearly constant
i. Normal structure loading of building has built in static loads
ii. Typically, these loads are unchanged in the building unless structural supports fail

24
Q

What is a building/fire code?

A

a. Delineate the level of risk a community will face in regard to building failure
b. Building codes can be specific or general.

25
Q

What are specification codes?

A

i. Establishes building construction requirements through particular methods and materials
ii. Example: one possible specification code might require a fire wall to be made completely out of masonry

26
Q

What are performance codes?

A

i. Sets a requirement for performance that must be met.
ii. Does not limit the selection of materials and systems used as long as they meet the performance requirement
iii. Example: The code may require a certain firewall to withstand 2 hours of fire exposure without failure

27
Q

Why do we care about the code the city is under?

A

i. The use of trusses and other engineered materials came about with the advent of performance codes.
ii. Under a specification code, the builders were required to use certain size beams to support certain loads.
iii. Under a performance code, the builders could use a TGI beam in place of a full size beam and support the same load

28
Q

What’s the difference between a fire code and building code?

A

i. Building code regulates how things are constructed and is not normally applied retroactively unless renovations or remodeling occurs.
ii. Fire code regulates use of building after it has been constructed, and is applied retroactively even to building hazards that existed prior to adoption of the fire code.

29
Q

What code do we use?

A

i. International building code 2012 edition
1. With local amendments.
2. Largely a performance-based code
3. Places emphasis on the metric system
4. Called the Tucson Fire Code
a. Updated every 3 years
b. Not a law until accepted by the local government
c. 2015 edition is out, but we haven’t accepted it yet.

30
Q

How are code improvements brought about?

A

i. Advance in technology tested and proved by independent testing agencies and submitted to ICC for approval in code.
ii. Changes also brought about through history by events creating large losses of life.

31
Q

Iroquois Theatre fire

A

a. 1903, 602 dead

b. Led to code changes requiring panic exit devices for emergency egress

32
Q

Coconut Grove

A

a. 1942, 492 dead
b. Led to code changes requiring visible exit signs, outward opening exit doors, and limited the amount of flammable decorations.

33
Q

Beverley Hills Supper club

A

a. 1977, 165 dead

b. Led to code changes limiting aluminum wiring and required fire alarms to have an audible evacuation tone

34
Q

Happyland Supper club

A

a. 1990, 87 dead

35
Q

Our lady of angels Catholic School

A

a. 1958, 95 dead

36
Q

Rhythm night club

A

a. 1940, 203 dead

37
Q

Triangle shirt waist factory

A

a. 1911, 146 dead

38
Q

Code limitations

A

i. Adopting a code alone does not guarantee safety
ii. Education and enforcement are as important as the code itself
iii. For example, the Station Nightclub fire
1. 2/20/2003, West Warrick RI
2. Pyrotechnics during the opening of Great White concert started fire
3. 100 dead, 230 injured
4. Originally a restaurant and exempt from sprinkler requirement
5. Sprinkler requirement was missed when changed to a nightclub

39
Q

Tucson AZ code inspections

A

i. Not enough inspectors to inspect every building on a regular basis
ii. Last estimate was 10 years between inspections
iii. For our safety, preplanning is a must!

40
Q

Classifcations of buildings is based on what?

A

a. The IBC classifies buildings based on occupancy type and construction
b. In general, the more flammable the construction type, and/or the more dangerous the occupancy type, the more stringent the building and fire code requirements.

41
Q

What are the types of building classification?

A

i. Assembly
ii. Business
iii. Educational
iv. Factory
v. High hazard
vi. Institutional
vii. Mercantile
viii. Residential
ix. Storage
x. Utility and miscellaneous

42
Q

Five types of standard construction

A

i. Type V: wood frame
ii. Type IV: heavy timber
iii. Type III: Ordinary construction
iv. Type II: Non-combustible
v. Type I: Fire Resistive

43
Q

Type V construction

A

wood frame

  1. Balloon frame: long timber going from floor to second story
  2. Platform: each floor is built independent of each other.
44
Q

Type IV construction

A

heavy timber

  1. Columns are minimum 8x8
  2. Beams are minimum 6x6
45
Q

Type III construction

A

Ordinary construction

  1. Main street USA
  2. Weakest point is the adjoining parts, such as bracket
46
Q

Type II construction

A

Non-combustible

  1. Metal frame structure covered by metal exterior walls. (Butler building)
  2. Metal frame structure enclosed by masonry
  3. Masonry bearing walls supporting a metal roof
47
Q

Type I construction

A

Fire Resistive

  1. Structural elements are protected from fire exposure via encasement, encapsulation, or membrane
    a. Encasement is enclosing in a fire resistant enclosure such as fire rated drywall.
    b. Encapsulation is coating the elements in a fire resistive material (intumescent paints that are sprayed on)
48
Q

Much ado about trusses…

A

a. Size up error with timber truss roofs
i. Not recognizing the presence of a truss roof
ii. Lack of heat give a false sense of security
iii. Conflicting reports
iv. Low fire load?
b. “In case of a lightweight truss roof, if there is enough heat and fire to require ventilation, the roof is unsafe; firefighters ventilating the roof should be supported independently of the roof.” - Francis Brannigan

49
Q

What is a CODE RED and what is done?

A

a. When anyone on the fireground sees or suspected a building collapse, a CODE RED is initiated by a group/division supervisor or the IC
b. Fire Alarm will announce the CODE RED by sound 5 one second tones one second apart, followed by “Code Red Sector NAME” then repeat it in one minute

50
Q

Firefighter duties in a CODE RED

A

i. Take only the equipment that you will need to exit the building.
ii. Do not risk your life, delaying your exit, removing hoseline, equipment, etc.!!!

51
Q

Engineer duties in a CODE RED

A

i. 15 second solid blast on air horn

ii. May surge hand lines

52
Q

Captain duties in a CODE RED

A

i. Conduct a PAR

ii. Group/division supervisors will account for all crews in their area

53
Q

What are some more building construction safety principles to be mindful of?

A

i. Collapse zone is 1-1.5
ii. Never cut principle support members
iii. Light weight construction = less mass = less time
iv. Trusses = less mass = less time