florida public model overvie · roof cover (shingle) pressure miami dade tests ... – claim...

Florida Public Model Overview

ProgrammingTeam

MeteorologyTeam

EngineeringTeam

ActuarialTeam

Provide probabilistic wind field info

Given wind, predict damage

Filter damages into annualized $

Research Objectives

Determine types Quantify wind resistanceTranslate wind speed into loads

Monte Carlo Simulation

% Quantify damages

FLORIDA EXPOSURE

2 major building categories

1. Single Family Homes2. Mobile Homes

Data from county tax appraiser databases

• Year built• Number of stories• Roof type• Exterior wall type• Roof cover materials• Area

Model Types in Four Regions

• The different model types and their characteristics are based on the population statistics in each region.

Resulting Classification

Roof Cover Roof Type Exterior Wall

Number of Story

Shingle Gable Wood frame

1

Tile Hip Masonry 2

Others Other Other more

Research Objectives



% Quantify damages

Wind Speed Wind Load

• Translate wind speed to the pressures and forces on the building

Component Wind Loads

InputDiscrete 3 sec

wind speed(e.g.V = 110 mph)

OutputComponent

loads/pressures(e.g. one sheathing panel)

• Sources:– Wind load provisions in code– Directional modifications– Full scale measurement

• Influences:– Building shape– Wind direction


• C&C pressure coefficients, re-mapped

Wind

ASCE 7-98 Zone 3

ASCE 7-98 Zone 2

ASCE 7-98 Zone 1


• C&C pressure coefficients, re-mapped

ASCE 7-98 Zone 3

ASCE 7-98 Zone 2

ASCE 7-98 Zone 1

Wind

Load Paths

• Relate loads on outside of building to internal members and connections

Research Objectives



% Quantify damages

Component Resistance to Wind

• For each structural type– Identify major

components– Model the capacity of

each component– Determine Load Paths

Residential Components

• Type: e.g., Concrete Block, Gable Roof

• 5 Selected components– Roof cover– Roof sheathing– Roof to Wall

Connections– Walls (frame, masonry)– Openings

Openings

Roof SheathingRoof Cover

Roof to Wall Connections

WallsOpenings



Walls

Component Criteria Source Roof Cover (Shingle) Pressure Miami Dade tests Roof Sheathing Pressure In-situ testing by Clemson Univ. Roof to Wall Connection Uplift Simpson StrongTie

Bending & uplift Test data: Texas Tech Univ. Masonry Shear Masonry code Bending Natl Design Specification Uplift Test data: Clemson Univ.

Walls Wood

Shear Natl Design Specification Pressure ASTM spec. Windows Impact Poisson distr.

Doors Pressure Engineering judgment Openings

Garage Pressure Manufacturer’s association

Component Capacity –Quantify Strength

• Capacity information for each component is described by a probability curve (PDF)

• 3 sets of models: – weak – medium– strong

• Reflect different eras in building code development and practice

Different Strength Models

Model Differences

Model Garage door

Sheathing nailing

Roof to wall connections

Roof shape

Opening protection

Weak Weak(30 psf)

6d(55 psf)

Toe nails(see next)

Gable or hip

None or plywood

Medium Weak(30 psf)

6d(80 psf)

Clips(see next)

Gable or hip

None or plywood

Strong Strong(52 psf)

8d(130 psf)

Straps(see next)

Gable or hip

None or plywood

Note : Plywood reduces probability of missile impact damage by 50%


Presented as non gable end capacity/gable end capacity all in lbs.Numbers are multiplied by a factor of safety = 3.0

Wall type Toe nail Clip strap

Wood wall 460 / 380 690 / 650 1240 / 1260

Masonry 700 / 225 1065 / 640 1400 / 640

Mitigation

• The model has the capacity to model different mitigation measures either individually or in combinations

• Details are provided in discussion of form V-2

Manufactured Homes

Types modeled:– Pre-HUD Code:– Post-HUD Code (1994)

7 ft

Research Objectives



% Quantify damages

INPUT

Random 3 secwind speed

(e.g.V = 110 mphWith COV = 0.1) LOAD: Modified Pressure

Coefficients from ASCE 7Randomized using COV = 0.1

Openings



Walls

DAMAGE

Random componentcapacities

Monte Carlo Simulation Engine

Monte Carlo Simulation Engine

• Create a typical house– Resistance from PDFs– Unique value for each

window/door/panel

psf• Apply hurricane wind load– 3-sec gust– Wind speed loads

• Investigate failures– Compare load to resistance– Failures may change loads

iteration

Iterative failure check procedure

• Internal pressurization due to breach• Roof-to-wall connection redistribution

x

Damage Prediction

• Damage Matrix for:

– Each structural type

– Wind speeds 50 – 250 mph in steps of 5 mph

– Eight wind directions

Example Damage Matrix

• Partial sample of an output file for a concrete block home, in South FL, with a gable roof, and no hurricane shutters, subjected to a 150 mph 3-sec wind gust at an angle of 45 degrees

Research Objectives



% Quantify damages

Cost Estimation Model %

• From the Damage Matrices– Convert modeled physical damages into monetary

damages– Define the vulnerability of different homes types– Provide a logical method for prediction damage to

other coverage’s– Validate the damage predictions – Input from experts (adjusters, etc.)

Different Types of Damage %

Exterior

Damage

Interior

Damage

Utilities

Damage

Contents

Damage

Additional

Living Expenses

Stage 1 Stage 2 Stage 3

Building

Damage

Appurtenant

Damage

Cost Estimation

• Replacement RatiosReplacement Cost Ratio's for a Masonry home, with a Shingle roof, and Hurricane Shutters

Approximate Replacement Costs

Replacement Ratios

Foundation/Slab 7,884$ 6%Roof Sheathing 6,205$ 5%Roof Cover 9,500$ 7%Trusses 11,704$ 9%Exterior Walls 28,486$ 21%Windows 5,012$ 4%Shutters 3,138$ 2%Entrance Door and Sliding Back Door 1,172$ 1%Garage 1,182$ 1%Interior 44,240$ 32%Plumbing 13,261$ 10%Mechanical 8,423$ 6%Electrical 8,333$ 6%Total 148,539$ 108%

%

• Interior, electrical, mechanical, and plumbing systems comprise a significant value

Cost Estimating Resources• Collections of average unit costs for

materials, labor, and equipment based on contractor bids for typical projects– CEIA Cost 2003– RSMeans Residential Cost Data – National Construction Estimator– 2004 National Renovation & Insurance Repair

Estimator – Marshall & Swift– Claim settlement info

%

Vulnerability Matrices• Model Type - Specific to each Monte Carlo model (36 models) plus

additional considerations for each (6*36 = 216)

Damage\Wind Speed (mph) 48.5 to 52.5 52.5 to 57.5 57.5 to 62.5 62.5 to 67.5 67.5 to 72.5 0% to 2% 1 0.99238 0.91788 0.77312 0.61025 2% to 4% 0 0.00725 0.0805 0.21937 0.36138 4% to 6% 0 0.000375 0.001375 0.007 0.0235 6% to 8% 0 0 0.000125 0.000375 0.0025 8% to 10% 0 0 0 0 0.000375

10% to 12% 0 0 0 0 0.000375 12% to 14% 0 0 0 0 0.000625 14% to 16% 0 0 0 0 0.0005 16% to 18% 0 0 0 0 0.000125 18% to 20% 0 0 0 0 0.000125 20% to 24% 0 0 0 0 0.00025 24% to 28% 0 0 0 0 0

Weighted Vulnerability Matrices

• Matrices are designed to make use of more information than provided in the insurance files

• Weighting based on:– Roof cover– Roof shape– Number of stories– Opening protection

• Additional weighting based on age when year built not present (e.g. Cat fund)

Masonry Structures VulnerabilitiesNorth WBDR Concrete Building Vulnerabilities

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

50 70 90 110 130 150 170 190

wind speed (mph) 3s

Dam

age

Rat

ios

StrongMediumWeak

Masonry Contents VulnerabilityNorth WBDR Concrete Contents Vulnerabilities

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

50 70 90 110 130 150 170 190

wind speed (mph) 3s

Dam

age

Rat

ios

StrongMediumWeak

Masonry ALE VulnerabilityNorth WBDR Concrete ALE Vulnerabilities

0%

5%

10%

15%

20%

25%

30%

35%

40%

50 70 90 110 130 150 170 190

wind speed (mph) 3s

Dam

age

Rat

ios

StrongMediumWeak

Manufactured Homes Structure VulnerabilitiesManufactured Homes Structure Vulnerabilities

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

50 70 90 110 130 150 170 190 210 230 2503 sec gust wind speeds

Dam

age

Rat

ios

central pre94 07

Post94-III, 07

Post94-II

Questions ??

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