Florida Coastal Monitoring ProgramFlorida Coastal Monitoring ProgramHurricane Wind Data CollectionHurricane Wind Data Collection

Kurt Gurley – University of FloridaForrest Masters – Florida International University

Tim Reinhold – Institute for Business and Home SafetyDavid Prevatt – Clemson University

Florida Coastal Monitoring Program

• Measure in-field hurricane ground level wind velocities and relay data in real-time to emergency managers, forecasters and researchers

• Measure the hurricane wind pressures on residential structures

• Test capacity of building components

• Statistical Assessment of structural damage post-event

• Model structural vulnerability, and investigate mitigation measures

Knowledge of ground-level winds used by:

– Atmospheric scientists • Boundary layer transition during hurricane landfall• Peak and mean speeds for model calibration• Validation of remote sensing technology

– Emergency managers• Estimate

– Physical damage (buildings and lifelines)– social and economic impacts

• Assignment of limited resources

Motivation for Research

Motivation for Research

Knowledge of ground-level winds used by:

– Wind and civil engineers• Modeling the Damage Chain

– Wind speeds at higher elevations– Wind speeds near ground level– Wind pressure on structures– Wind damage prevention measures

• Outcomes:– Wind tunnel modeling– Building codes and standards with accurate load

information

Portable Weather Stations

• Stiff 10-m Steel Lattice Tower

• Remain stable in 200 mph winds

• Self-powered

• Instruments collect wind speed and environmental data

• Quick setup to hasten retreat from approaching storm

Tower in Atlantic Beach, NCIsabel, 2003

Navarre Causeway

Dennis 2005

Peak 3-sec gust of 120 mph at 5 meters

Tower Data

Time histories of wind speed over the duration of the hurricane

Statistical analysis reveals information needed for engineering design to resist the wind

Real-time Data Transmission

NOAADCS

MIRRORWEB SERVERS

FIELD NOAA

GOES SATELLITE

NOAA Hurricane Research DivisionMaximum Sustained Wind Swath

Hurricane Jeanne (2004)

Tower data is one of the sources of ground data input to H*WIND contour model of wind speeds

Fleet of 5 towers (6 for 2006 season)

Program Website www.ce.ufl.edu/~fcmp

FCMP Instrumented Homes Measure Hurricane Wind Pressure

• 32 homes along Florida coast• Owners receive free retrofits

– storm shutters, new roof, gable bracing, braced garage door, etc.

• Sensors record uplift roof pressure

Hurricane FrancesWinds on House – Jensen Beach

Study to Compare full-scale to Wind tunnel model to ASCE 7 loads

Hurricane FrancesWinds on House – Jensen Beach

Frances Peak 3-sec Gusts

Hurricane Frances Eye Wall

Eyewall Peak 3-second gust 82 m.p.h.

Ivan: Category 3 ? Not Based on Measurements

102 mph71 mph

75 mph

109 mph

124 mph

107 mph

107-119 mph

109 mph

106 mph

96-107 mph

81 mph

75-85 mph

86 mph

89 mph

89 mph

Jeanne Peak 3-sec Gusts

Wilma Measured Peak Winds

Structural Resistance

Using real houses being demolished

– In-field testing to quantify actual loads to failure

– Relate back to wind speed– Test as-built and retrofitted

Failure Capacity Testing

• DCA project to determine ultimate loads to failure for as-built and retrofitted structures

• As-built roof to wall toe-nail connections

Failure Capacity Testing

• Retrofit with modern roof to wall connections

• Uplift capacity increased by factor of 5 with simple retrofit

• Loads to be converted to wind speed

Post EventDamage Documentation

Jeanne, 2004

Post Event Damage Documentation

Window PerformanceCharley 2004 -Charlotte County

Computational Modeling of Structural Vulnerability

– Model the capacity of building components– Apply wind loads– Calculate probability of damage to building

Openings

Roof SheathingRoof Cover

Roof to Wall Connections

WallsOpenings

Roof SheathingRoof Cover

Roof to Wall Connections

Walls

Mitigation Studies

How would these curves (risks) change if we added strength?

– Hurricane shutters– More nails

Easily incorporated into the structural model

Leads to comparative cost effectiveness ($$)

May be applied to other types of structures

Openings

Roof SheathingRoof Cover

Roof to Wall Connections

WallsOpenings

Roof SheathingRoof Cover

Roof to Wall Connections

Walls

Thank you. Any questions?

Project website www.ce.ufl.edu/~fcmp