Cyclone Mitigation Research in and the U.S.

Queensland Florida

Global tracks from 1985 to 2005

Daniel J. Smith Cyclone Testing Station, Florida

*impact resistance windows

Hurricane Irma (tornado) Sept. 2017, Crescent Beach, FL Texas

Aged connections and poor maintenance

Hurricane Harvey (Cat. 4) August 2017, Holiday Beach, TX

Cyclone Debbie (Cat. 3) March 2017, Wilson Beach, QLD Aged connections and poor maintenance Cyclone Tracy (1974) Hurricane Andrew (1992)

• Peak gust estimated 243 km/h (71 Fatalities) • Peak gust estimated 281 km/h (65 Fatalities) • 70-90% of housing destroyed • >63,000 homes destroyed • Engineered structures performed better

Queensland Home Building Code (1982) Florida Building Code (2002) Building Codes for Design (FL vs QLD) *Design of openings a key difference

Large negative pressure Negative pressure on roof at windward edge

Large Internal Positive positive Negative pressure pressures pressure on on wall lee wall Housing Performance (FL and QLD)

Financial loss ($) target ?

Life safety target

Traditional Life safety goals ? construction achieved Tomorrow Performance

Stronger building codes

Catastrophic cyclones Post-war era (Tracy and Andrew) construction

1940s To d ay Time Pre1980s Housing and Cyclones in Australia

Northern Territory Western 40%Australia Queensland 60% South Australia New South Wales

Population Victoria Australia 24 million Australian Tasmania Florida 21 million Capital Queensland 5 million Territory

Western AU. 3 million Credit: Australian Geographic Post 1980s design wind speeds in Florida vs Australia

240 km/h

. 258 km/h *converted assuming = 1.147 𝑉𝑉0 2 3 277 km/h 𝑉𝑉

295 km/h

314 km/h Australia • 1:500 Annual probability of exceedance • 10% in 50 yrs prob of exceedance

250 km/h

330 km/h 300 km/h

205 km/h

Florida (ASCE 7-10) • 1:700 Annual probability of exceedance 162 km/h • 7% in 50 yrs prob of exceedance Weather Stations in Queensland

~400 km

~100 km Weather Stations in Florida (Hurricane Irma)

~400 km

Florida = 170,000 km2 Far North Qld = 381,000 km2

*3-sec gust not corrected for terrain/instrument height

0.2-sec gust * (<129 km/h) (129-148 km/h) (149-166 km/h) (168-185 km/h) ~100 km (186-222 km/h) Surface Weather Information Relay and Logging Network (SWIRLnet)

R.M. Young wind monitor

Auger drill

Optional guying system

Data logger and telemetry 3.2 m

800 mm ground screw 1 m

Ground screw anchoring Vulnerability Models Key considerations 1. Wind data analysis 2. Post-event damage investigations 2. Experimental testing 3. Claims analysis All have pros/cons, all are needed to get the full picture

13 Post-event damage investigations

Pros clear picture of damage Cons no $ loss, time constraints, exterior view only sometimes

Metal roofing failure from TC Debbie (2017) Water ingress damage from TC Larry (2006) Experimental Testing

Pros specific connection strength and fatigue data Cons realistic simulation difficult (e.g., load sharing, aging)

Retrofit testing for roof to wall connections Roofing tile clip testing for wind uplift Typical damage modes

100% Roller Door Tree 80% Window Water Damage 60% Roof

40%

Likelihood of Occurrence Likelihood 20%

0% 0-10% 10-50% >=50% (157 Samples) (52 Samples) (26 Samples)

Limitations  small sample sizes, more detailed analysis needed

www.jcu.edu.au/cts Vulnerability for Housing • Roofing, window, water ingress  dominate loss • Minor damages independent of housing age (high frequency) • 1925-1981 housing at relatively > risk of structural damage • Modern housing still vulnerable • Solutions exist (e.g. tie down straps, shutters, etc.) Recommendations for Mitigation 1. Structural roof upgrading 2. Opening (i.e. windows, doors, etc.) protection upgrading 3. Community education/outreach

www.jcu.edu.au/cts Investing in Mitigation?

New Roof?

New Kitchen? 19 Understanding Behavior Change …we need to think bigger

Mitigation Prior experience capacity? with events?

Understanding Financial of risk? incentive?

The “hassle What is my factor” neighbor doing?

20 MultidisciplinaryThank and you! Collaborative