Design criteria for public cyclone shelters
Transcript of Design criteria for public cyclone shelters
Design criteria for public cyclone shelters
EHA – WA Conference, Sept 2015
Dr Peter MullinsMullins Consulting
Brisbane
TC Yasi
2nd Feb 2011
Evacuation
EHA – WA Conference, Sept 2015
• Storm tide inundation
• Vulnerable houses
Tully
TC Yasi Feb 2011
Harvey Bay Storm Tide
Model
Yeppoon
TC Marcia Feb 2015
Shelter options
EHA – WA Conference, Sept 2015
• Leave
• Shelter in modern home
• Shelter in public buildings
Innisfail
TC Yasi Feb 2011
Cairns
TC Yasi 2011
Existing public buildings
EHA – WA Conference, Sept 2015
Tully Senior Citizen Hall
TC Yasi Feb 2011
Innisfail SHS
TC Larry 2006
Innisfail SHS
TC Larry 2006
Purpose built cyclone shelters
EHA – WA Conference, Sept 2015
Redlynch SC
Tully SS
Innisfail SHS
Proserpine SS
Design criteria
EHA – WA Conference, Sept 2015
• Siting
• Design actions
• Building elements
• Access, occupancy and egress
• Fire safety
• Health and amenity
• Ancillary provisions
• Design and construction assurance
Siting
EHA – WA Conference, Sept 2015
• Storm tide hazard (1:10,000 storm tide)
• River and creek flood (Q500)
• Landslip hazard (risk to life VL, to property L or VL)
• Proximal hazards (buildings, trees, hazardous materials)
• Vehicle and pedestrian corridors (accessible to community)
• Limited use helicopter landing site (eg. sports oval)
Storm tide hazard
EHA – WA Conference, Sept 2015
Above the evacuation zone for the 1 in 10,000 storm tide
Uncertainty in cyclone track – location and time – increases evacuation zone.
Greater length of coast is evacuated due to uncertainty of landfall.
Forecast storm tide is based upon the highest tide of the day
Design actions
EHA – WA Conference, Sept 2015
• Wind speed
• Wind borne debris
• Permanent and imposed
• Earthquake
• Wave and flood flow (applicable to lower levels of a shelter on
a sloping site with access to ground beyond the evacuation zone and
flood inundation)
Wind speed
EHA – WA Conference, Sept 2015
Annual probability of exceedance of 1 in 10,000.
Probability at a single location.
Probability increases with number of locations.
Australian Standards Wind Code (AS1170.2)
Region C: V10,000 = 306 km/hr
Region D: V10,000 = 392 km/hr
Wind borne debris
EHA – WA Conference, Sept 2015
100x50 timber member of 4kg mass impacting at
• 0.4V10,000 horizontal trajectory (Region C 122km/hr; Region D 157km/hr)
• 0.1V10,000 vertical trajectory (Region C 31km/hr; Region D 39km/hr)
Load B: 8mm diameter steel balls impacting at
• 0.4V10,000 horizontal trajectory (Region C 122km/hr; Region D 157km/hr)
• 0.3V10,000 vertical trajectory (Region C 92km/hr; Region D 118km/hr)
Kurrimine Beach
TC Larry 2006Innisfail SHS
TC Larry 2006
Wind borne debris – Tests
EHA – WA Conference, Sept 2015
solid core door 50mm plywood door steel clad door
4kg impacting at 122 km/hr
Building elements
EHA – WA Conference, Sept 2015
• Roof
• External walls & doors
• Debris screens, windows and louvers
• Internal ceilings, partitions and doors
• Site drainage
• Element certification and testing
Roof
EHA – WA Conference, Sept 2015
• Design to resist wind and wind borne debris
• Roof slope < 15 degrees to avoid horizontal trajectory debris missile.
• Screw fixed.
• Design building shape to reduce wind pressures.
• Drain roof water Q500
Internal ceilings partitions and doors
EHA – WA Conference, Sept 2015
Suspended ceiling
hanger rods do not
resist positive
internal pressure.
X
Construct ceiling and internal partitions to resist internal
wind pressures.
Install ventilation grills in doors and hatches in ceilings to
reduce differential internal pressures.
Access, occupancy and egress
EHA – WA Conference, Sept 2015
• Location and building signage
• Access and safe movement
• People with disabilities
• Occupancy
• Occupancy duration
• Egress- Alternative building
solution
Occupancy
EHA – WA Conference, Sept 2015
Design capacity based upon:
• 1 person per 1.2 m2 of shelter floor area
• 50 people per toilet
Design occupancy period:
• Total occupancy period 36 hrs
• A lockdown period of 18 hrs
Fire safety
EHA – WA Conference, Sept 2015
• Fire resistance and stability
• Compartmentation and separation
• Smoke detection and alarm system
• Fire hose reels
• Automatic fire suppression system
• Fire extinguishers
Compartmentation and separation
EHA – WA Conference, Sept 2015
Main electrical switchboard, emergency power switchboard,
diesel generator, emergency lighting batteries and
uninterrupted power supply to be smoke and fire separated
from the shelter space with fire resistance levels (FRL) of
120/120/120.
Fire hose reels and Fire extinguishers
EHA – WA Conference, Sept 2015
Fire hose reels to be located
inside the building
Additional fire extinguishers
within the shelter
Health and amenity
EHA – WA Conference, Sept 2015
• Ventilation
• Water and weather proofing
• Lighting
• Power distribution
• Lightning protection
• Emergency power
• Toilets and shower amenities
• Stored water supply
• Waste water
Ventilation
EHA – WA Conference, Sept 2015
Naturally ventilated during lockdown when the wind gust are
gale force or greater (100 km/hr gusts)
Ventilation
EHA – WA Conference, Sept 2015
Venturi duct extraction to toilets
Manual louver and
damper controls
Natural ventilation ducts with
baffles, wall and ceiling fans
Ventilation, water and weatherproofing
EHA – WA Conference, Sept 2015
Construct
Baffles on inside of louvers
Roller shutters on outside of louvers
Two stage louvers with plenum for natural ventilation
Sarking to roof
Ancillary provisions
EHA – WA Conference, Sept 2015
• Communications
• Seating and emergency bedding
• Kitchen
• Shelter office
• Emergency first aid
• Chair store
Seating and emergency bedding
EHA – WA Conference, Sept 2015
Yeppoon Cyclone Shelter – TC Marcia Feb 2015
Design and construction assurance
EHA – WA Conference, Sept 2015
• Buildings normal use• NCC (incl Building Code of Australia)
• Cyclone shelter use• Cyclone shelter design guidelines
Other guidelines
EHA – WA Conference, Sept 2015
Mitigating the adverse impacts of cyclones:
Evacuation and shelterDisaster Management Act 2003 Guideline
Queensland Public Cyclone Shelters
Maintenance GuidelinesDisaster Management Act 2003 Guideline
Queensland Public Cyclone Shelters
Operations GuidelinesDisaster Management Act 2003 Guideline