Tall Wood Building Project
Xiao Li
With,
Alejandro Medina
Prof. George Hadjisophocleous
Andrew Harmsworth
Christian Dagenais
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1
Fire Risk Modeling using CUrisk
 The objective is using CUrisk to
compare the fire risk of the proposed
combustible building with the fire risk
of a non-combustible building.
 Buildings for comparison:
• The proposed combustible construction
• 15% of total room surface area non-protected
(1 wall exposed)
• A comparable non-combustible
construction
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Fire Risk Modelling
 In the 2nd meeting:
• Results of fire risk analysis based on fires
on the 2nd floor.
• Fire growth in the fire room
• Effects of sprinklers and fire department
on fire development
• Effects of CLT wall exposure areas on fire
development
• Effect of reliability of fire sprinklers on the
fire risk of the building
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Outline
 CUrisk modeling results today
• Fire Scenarios covering all the floors
• Normal scenarios in the residential floors
• Extreme fire scenarios (lobby fire and night
fires)
• Response and Evacuation process
• Probability of evacuation following response
• Remaining percentage of building occupants
• Occupants Evacuation times
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4
Floor Plan
Commercial
Rooms
Commercial
Rooms
Lobby
2-BedRm
Apt.
Lobby
Commercial
Rooms
Commercial
Rooms
Ground floor plan
1-BedRm
Apt.
2-BedRm
Apt.
Corridor
2-bedroom
Apt.
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1-BedRm
Apt.
2-BedRm
Apt.
Residential floor plan
2nd to 20th storey
Occupant loads
31 p
31 p
 According to building code
Dwellings:
2 person per sleeping room
Mercantile uses:
3.7 m2 /person
First storey
31 p
31 p
 Occupant loads
First storey: 124 persons
Residential storey: 20 persons
Totally in the building:
504 occupants
4p
4p
other storey
4p
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6
2p
2p
4p
Fire Scenarios
 Residential Fires in
all the residential
storeys
•
•
•
•
•
Apt 11 on 2nd floor
Apt 18 on 3rd floor
Apt 25 on 4th floor
…
Apt 137 on 20th
floor
Scissor stairs
 Extreme scenarios
• Fire In the lobby on
the first floor
• Night fires without
fire suppression
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fire
Apt.11
Occupant response to fire
Proposed combustible construction
When detectors/alarms
are available
Average Probability of Evacuation
1.0
0.8
Proposed
combustible
construction
0.6
Non-combustible
construction
0.4
0.2
0.0
0
2
4
6
8
10
12
14
Time (minutes)
Probability of evacuation following occupant response time
when fire occurs in room 11 on the 2nd floor
No fire suppression and detection and alarms (solid and dash lines)
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8
Occupant Remaining Percentage in the Building
Evacuation Remaining percentage
100
80
Non-combustible building
60
40
Proposed
building
20
Proposed building,
when Detectors /Alarms
0 are available
0
5
10
15
20
Time (minutes)
Occupant remaining percentage in the building versus time
when fire occurs in room 11 on the 2nd floor
No fire suppression and no detectors and alarms (red and black)
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Occupant evacuation times
Storey number
Average Evacuation Time (minutes)
16
1
2
3
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20
20 p
on each residential floor
124 p
on 1st floor
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4
12
Non-Combustible
building
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4
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Proposed building
when detectors and alarms
are available
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2
2nd floor
0
1
101
201
301
401
504
Occupant Number
Average evacuation time for each occupant (among 504)
when fire occur on 2nd storey room 11
A comparison of the proposed combustible building and a non-combustible building
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Fire risk comparison
 Considering possible
fire senarios on each
residential floor
•
Room fire
Sprinkler
1/19
0.95
0.8
Same probability
occurring on each floor
 Considering reliability of
•
•
•
sprinklers,
detector/alarms and,
Fire Department actions
 Totally 152 fire
scenarios for each type
of building
•
•
Detector
and
Alarm
Fire
Depart.
0.7
Scenario
Probability
Y
0.024
N
0.016
Y
0.006
N
0.004
Y
0.0013
N
8.4e-4
Y
3.16e-4
N
2.1e-4
Y
Yes
A Fire on
each
residential
floor
N
19 storeys
Y
The proposed building
Comparable noncombustible building
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11
No
N
Expected fire risk comparison
10
Non-Comb 8
6
4
Proposed
2
building
0
0.4
0.3
0.2
0.1
0
Expected Casualties
(person)
Expected Casualties when a fire occur on any
residential storeys among all the occupants (504)
Expected Fire
Loss (k$)
Expected Fire Loss when a fire occur on any
residential storeys in the whole building
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12
Extreme fire scenarios
 Low probability of occurrence
 Fires in the lobby
 Night fires where fire suppressions systems
are not available
 Earthquake induced fires are not considered
due to its complexity, but comments may be
provided.
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13
Fire in the lobby
 CUrisk results showed that:
 Fire in the lobby can cause
hundreds of casualties and a lot
more damages due to fire spread
to adjacent heavy-loaded shops
 Smoke and heat block all the
exits
 However, fire spread to upper
storeys may be limited in the
podium because of its noncombustible construction and
remote window openings from
upper storeys (vertical external
fire spread)
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14
Lobby
Lobby
Fires at night without fire prevention
 Worst scenarios when no fire
suppression and detection
system
 Compared with daytime fires
without fire prevention
 Expected overall risk by
considering possible scenarios
on every residential floors (19
fire scenarios)
 Results show fire losses are
same but night fires may cause
lots more casualties than
daytime fires.
10
5
0
Casualties
(person)
Daytime
Night Fires
300
200
100
0
Fire Losses (K$)
Comparison of Expected risk between daytime fire
and night fires in the proposed building.
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15
Reliability of Sprinklers
 Last meeting showed that reliability of
sprinklers is the most important factor in
reducing the fire risks.
 When sprinklers are installed and work
reliably (P_Sprinkler = 1) :
Risk (proposed building) ≈ Risk (Non-combustible building)
 Possible solutions:
• Fast response sprinklers with high reliability and
suppression efficiency
• Reliable fire detectors and alarms that can
provide quick fire cues to occupants.
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16
Summary
 Possible fire scenarios are simulated on all the residential
storeys, and results showed that fire risk of the proposed
building is close to (or slightly higher) than the noncombustible building.
 Evacuation simulation results showed that occupants can
evacuate out of the building with a reasonable time
frame; and occupant evacuation times in the proposed
combustible building are slightly shorter than a
comparable non-comb. building.
 Again, high reliability sprinklers (good efficiency) can
prevent the fire in its infancy, thus can avoid faster fire
growth in the combustible compartment (especially in
the case of wood panel exposure).
 Fire in extreme scenarios may cause significant life risks
and fire losses, though occurrence probabilities are low.
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