Post on 25-Apr-2020
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Curt B. Haselton, PhD, PEProfessor of Civil Engineering @ CSU, Chico
Co-Founder @ Seismic Performance Prediction Program (SP3)
www.hbrisk.com
Resilience-Based Design & Risk Management using FEMA P-58
Recent Developments, Recent Adoption on Projects, and the Future
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Quick orientation to FEMA P-58 and applications Recent innovative projects being done using this
new FEMA P-58 methodMore detail on the FEMA P-58 methodDesign example Plans for future work and development
Agenda for Tonight
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FEMA P-58 is a probabilistic performance prediction methodology (10+ years in the making, $12M+ invested, development ongoing)
FEMA P-58 is tailored for building-specific analysis (in contrast to most risk assessment methods)
FEMA P-58 output results:• Repair costs• Repair time• Safety: Fatalities & injuries
FEMA P-58
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FEMA P-58 Modeling Approach
Ground Motion Hazard
Component DamageEconomic Loss
Casualties
Repair Time
Structural Response
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FEMA P-58 Applications
New design (resilience-based design)
Retrofit
Risk evaluations for mortgage (PML) and insurance
Risk evaluations for specialized buildings
Building ratings
Applications: Code design (safety-only and
prescriptive), performance-based design (typically also safety-only)
ASCE 41 (mostly safety-only, except for if using IO)
Experience and judgement-based approaches, which do not handle much building-specific information (e.g. Hazus, ATC-13, ST-Risk, SeismicCat, etc.).
[same as above]
Ratings are new; can use FEMA P-58 methods or checklist-based)
Contrasting Methods:
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Code Design (ASCE7, etc.) Safety Goal - Yes
“Performance”-Based Design (AB 083, ASCE 41, etc.) Safety Goal – Yes Also enhanced modeling and design scrutiny
“Resiliency”-Based Design (and Risk Assessment) Safety Goal – Yes Repair Time Goal – Yes Repair Cost Goal - Yes Also enhanced modeling and design scrutiny
Design and Assessment Methods
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Recent Innovative Resiliency/Risk Projects
In my book, these are exciting times.
I am excited about what is starting to be
done with FEMA P-58 for resilient design
and enhanced risk assessment.
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Recent Innovative Resiliency/Risk Projects
New Design: Long Beach Civic Center
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Recent Innovative Resiliency/Risk Projects
New Design: Long Beach Civic Center
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Recent Innovative Resiliency/Risk Projects
Retrofit Projects: San Francisco, Sacramento, etc.
Figure: https://en.wikipedia.org/wiki/List_of_tallest_buildings_in_San_Francisco
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Recent Innovative Resiliency/Risk Projects
Risk Assessments: Property Transaction Due-Diligence
FEMA P-58 can be used for PMLs, but also for much more detailed risk
assessments as well (accounting for the building-specific properties, etc.).
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Recent Innovative Resiliency/Risk Projects
Risk Assessments: Property Transaction Due-Diligence
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Recent Innovative Resiliency/Risk Projects
Risk Assessments: Detailed Assessments of High-Value Items
Risk to high-value content.
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Recent Innovative Resiliency/Risk Projects
Risk Assessments: Detailed Assessments of High-Value Items
Post-earthquake operability of production facilitates.
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Recent Innovative Resiliency/Risk Projects
Assessments for Innovating Structural Systems
Figures: http://cenews.com/userfiles/image/SE1111_44.jpg
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Recent Innovative Resiliency/Risk Projects
Assessments for Innovating Structural Systems
Figures: http://cenews.com/userfiles/image/SE1111_44.jpg, http://precast.org/wp-content/uploads/2010/09/defying_rubber_band.jpg
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Recent Innovative Resiliency/Risk Projects
Assessments for Innovating Structural Systems
Figures: http://img.archiexpo.com/images_ae/photo-g/55901-3675379.jpg
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Recent Innovative Resiliency/Risk Projects
Assessments for Innovating Structural Systems
Figures: http://img.archiexpo.com/images_ae/photo-g/55901-3675379.jpg
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Building ratings and the U.S. Resiliency Council rating system:• articulates FEMA P-58 results to star ratings (e.g. < 5% cost is 5-star).• is useful to communicate performance simply (and my hope is that it
will lead to a push for more resilient design).• is fully implemented in SP3 (SP3 will compute the rating).
Recent Innovative Resiliency/Risk Projects
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Building ratings and the REDi Rating System (also implemented in SP3):
Recent Innovative Resiliency/Risk Projects
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FEMA P-58: More Details Under the Hood
Ground Motion Hazard
Component DamageEconomic Loss
Casualties
Repair Time
Structural Response
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FEMA P-58: Ground Motions
Step 1: Define ground motion hazard curve (with soil type)• Option #1: SP3 can provide for the U.S. (given an address)• Option #2: User-specified
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FEMA P-58: Structural Response
Step 2: Predict “engineering demand parameters”
• Story drift ratio at each story• Peak floor acceleration at each
floor• For wall buildings, also wall and
coupling beam rotations
Option #1: Structural analysis
Option #2: Statistically calibrated predictive equations
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FEMA P-58: Component Damage
Step 3: Quantify component damageFirst, establish what components are in the building. Types and quantities of can be specified or estimated from building size and occupancy type
Windows Piping
Partitions Structural components
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We end up with a list of component types, quantities and locations
FEMA P-58: Component Damage
Step 3: Quantify component damage
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Each component type has a “fragility function” that specifies the probability that a structural demand causes damage
FEMA P-58: Component Damage
Step 3: Quantify component damage
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FEMA P-58: Consequences of Damage
Fragility functions have been calibrated for hundreds of components from test data, and repair cost and labor has been developed by cost estimators.
Cost per 100 ft. Labor per 100 ft.Cracked wallboard $2,730 24 person-hours
Crushed gypsum wall $5,190 45 person-hours
Buckled studs $31,100 273 person-hoursThese are median values—each also has uncertainty
Step 4: Quantify consequences of the component damage (component repair costs, repair times, etc.).
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FEMA P-58: Building-Level Consequences
Repair costs are the sum of component repair costs (considering volume efficiencies)
Recovery time is aggregated from component damage, but is more complex (mobilization, staffing, construction sequencing, …)
Windows $26,892Partitions $43,964
Piping $5,456
Structural Components
$77,920
… …
Sum = $253,968
Step 5: Aggregate to building-level consequences
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FEMA P-58: Monte Carlo Simulations
For a given building and ground shaking intensity, repeat the following steps several thousand times:
1. Simulate each structural response parameter2. Simulate damage to each component3. Simulate repair costs and repair time for each component4. Aggregate to compute total repair cost and recovery time
We can then look at the mean cost, 90th percentile, etc.
Step 5: Aggregate to building-level consequences
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FEMA P-58: Summary
Step 1: Site Hazard• Soil and hazard curve• Ground motions (if needed)
Step 2: Structural Responses• Option #1: Structural analysis• Option #2: Predictive equations
Step 3: Damage Prediction• Contents • Fragility curves
Step 4: Loss Estimation (loss curves) and other consequences
Step 5: Aggregate to building-level consequences
Thousands of Monte Carlo simulations
The simulations provide detailed statistical
information on building performance.
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FEMA P-58: Benefits
Standardized component fragilities and costs “Engineering-oriented” approach compliments actuarial
approaches Facilitates building-specific evaluations Provides detailed outputs of repair cost sources, etc.
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FEMA P-58: Summary
Step 1: Site Hazard• Soil and hazard curve• Ground motions (if needed)
Step 2: Structural Responses• Option #1: Structural analysis• Option #2: Predictive equations
Step 3: Damage Prediction• Contents • Fragility curves
Step 4: Loss Estimation (loss curves) and other consequences
Typical Reactions:
Looks extremely complicated!!!
Great method, but it’s a Cadillac and I
would only use it for special projects!!!
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The SP3 Software
A barrier to widespread FEMA P-58 adoption has been related to software and ease-of-use. FEMA P-58 is a great methodology but FEMA is expressly not in the
business of maintaining software. Software has been barrier to adoption. Need: To better enable use of FEMA P-58, a commercial-grade software is
needed. In 2014, Jack Baker and Curt Haselton decide to fill the software need by:
a) Creating user-friendly software to implement P-58. [released Dec. 2014] b) Maintaining software over time (fragilities, etc.). [e.g. working on some
expansions to fragility library now]c) Improving and extending the methodology in the future. [e.g. advanced
repair time estimates, enhanced method for structure responses, etc.]
ATC Coordination: We have been in coordination with ATC/FEMA from the start (so all pulling in same direction).
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The SP3 Software
Step 1: Site Hazard• Soil and hazard curve• Ground motions (if needed)
Step 2: Structural Responses• Option #1: Structural analysis• Option #2: Predictive equations
Step 3: Damage Prediction• Contents • Fragility curves
Step 4: Loss Estimation
USGS Soil and ground motion database
information embedded
Statistically calibrated structural response
methods are embedded
Building contents are auto-populated (using FEMA P-58 and enhanced options)
Structure: Cloud-based computational platform, flexible reporting options
Two-level structure: 1) Use initial pre-populated values2) Modify inputs and dig deeper
We implement the FEMA P-58 calculations, plus a
number of other features.
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8%
70%
16%
0% 3% 3% 0% 0%0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
StructuralComponents
Partitions InteriorFinishes
Cladding Plumbing andHVAC
OtherComponents
Collapse Residual Drift
Loss Contributions by Component Type for a 50 Year Ground Motion
Output Examples: Repair Cost
8-story concrete frame in Los Angeles
Loss Ratio = 0.04
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Output Examples: Repair Cost
8-story concrete frame in Los Angeles
37%32%
7%1% 1% 2% 1%
19%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
StructuralComponents
Partitions InteriorFinishes
Cladding Plumbing andHVAC
OtherComponents
Collapse Residual Drift
Loss Contributions by Component Type for a 475 Year Ground Motion
Loss Ratio = 0.15
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Output Examples: Repair Cost
8-story concrete frame in Los Angeles
26%
12%
2% 2% 0% 1% 3%
54%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
StructuralComponents
Partitions InteriorFinishes
Cladding Plumbing andHVAC
OtherComponents
Collapse Residual Drift
Loss Contributions by Component Type for a 2475 Year Ground Motion
Loss Ratio = 0.44
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FEMA P-58: Output Examples
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FEMA P-58: Output Examples
Average Repair Times (REDi, 2013):
0.8 0.9
3.5
0
2
4
6
8
10
12
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REDi Re-Occupancy REDi Functional Recovery REDi Full Recovery
MO
NTH
S
Repair Time Output at a 43 Year Earthquake
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FEMA P-58: Output Examples
Average Repair Times (REDi, 2013):
6.0 6.3
9.2
0
2
4
6
8
10
12
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REDi Re-Occupancy REDi Functional Recovery REDi Full Recovery
MO
NTH
S
Repair Time Output at a 475 Year Earthquake
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FEMA P-58: Output Examples
Average Repair Times (REDi, 2013):
10.7 11.0
13.1
0
2
4
6
8
10
12
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REDi Re-Occupancy REDi Functional Recovery REDi Full Recovery
MO
NTH
S
Repair Time Output at a 2475 Year Earthquake
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FEMA P-58: Output Examples
Average Repair Times (Figure Source: REDi, 2013):
10.7 11.0
13.1
0
2
4
6
8
10
12
14
REDi Re-Occupancy REDi Functional Recovery REDi Full Recovery
MO
NTH
S
Repair Time Output at a 2475 Year Earthquake
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FEMA P-58: Output Examples
Safety (fatalities and injuries):
0.20.0 0.0 0.0
0.20.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Injuries (FromFalling Hazards)
Fatalities (FromFalling Hazards)
Injuries (FromCollapse)
Fatalities (FromCollapse)
Total Injuries Total Fatalities
Mean Casualties at a 43 Year Earthquake
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FEMA P-58: Output Examples
Safety (fatalities and injuries):
1.3
0.0 0.0 0.0
1.3
0.00.0
0.5
1.0
1.5
2.0
2.5
3.0
Injuries (FromFalling Hazards)
Fatalities (FromFalling Hazards)
Injuries (FromCollapse)
Fatalities (FromCollapse)
Total Injuries Total Fatalities
Mean Casualties at a 475 Year Earthquake
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FEMA P-58: Output Examples
Safety (fatalities and injuries):
2.5
0.00.1
0.8
2.6
0.8
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Injuries (FromFalling Hazards)
Fatalities (FromFalling Hazards)
Injuries (FromCollapse)
Fatalities (FromCollapse)
Total Injuries Total Fatalities
Mean Casualties at a 2475 Year Earthquake
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The Big Picture – Quick Design Example
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• Project: Long Beach Civic Center• Building: Design a 11-story RC Wall (coupled core), office occupancy • Site: LA high-seismic, SDS = 1.1g, SD1 = 0.6g.• Design Objectives: Five-star performance in all categories
– Repair Cost < 5%– Functional Recovery Time < 5 days– Safety – high (low collapse, no/few injuries, good egress)
• Showing example for design, but also applicable to assessment.
Quick Design Example
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• Step #1: Start with code-compliant design to see where that gets us...
– Repair Cost = 8% [4-star]– Recovery Time = 6.5 months [3-star]
• 3.0 months – mechanical and electrical (HVAC, lighting, switchgear)
• 2.0 months – structural (mostly walls)• 1.5 months – non-structural drift-sensitive
(partitions, stairs, piping, fire sprinklers)– Safety [3-star]
(discussed at the end)
Quick Design Example
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• Step #2: Design wall to be “essentially elastic” (very strong)• Step #3: Design mechanical and electrical components to be
functional at the 10% in 50 year (anchorage, equipment, lighting, etc.).
• Result: – Repair Cost = 5.5% [still 4-star]– Recovery Time = 2.5 months [still 3-star]
• 1.0 month – slab-column connections• 1.5 months – partition walls
Quick Design Example
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• Step #4: Reduce the shear on the slab-column connections.• Step #5: Use less damageable partition walls.
• Result: – Repair Cost = 3.5% [now a 5-star]– Recovery Time = 6 weeks [still a 3-star]
• 3 weeks – slab-column connections• 3 weeks – partition walls
Quick Design Example
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• Step #6: Stiffen the building (longer walls, more coupling, etc.). Reduces the maximum drifts from around 1.4% to 1.0%.
• Result: – Repair Cost = 2% [5-star]– Recovery Time = 2 days [moved from
3-star to 5-star]
• Step #7: Now that building has less drift, move back to higher shear slab-column connections.
• Result: – Repair Cost = Still 2% [still a 5-star]– Recovery Time = Still 2 days [still a 5-star]
Quick Design Example
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• Step #8: Now that building has less drift, see if we can move back more damageable partition walls.
• Result: – Repair Cost = 2.5% [5-star]– Recovery Time = 2 weeks [would
moved down to 4-star]
**Move back to less damageable partition walls to keep a 5-star recovery time.
Quick Design Example
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• Step #9: Safety checks
• Overview of safety checks:– Fatalities. Show good collapse safety (limit fatalities).– Injuries. Check injury prediction from FEMA P-58 (would require
additional non-structural bracing to get to 5-star). – Residual Drifts. Very low (essentially elastic).– Stairs and Egress. Check probability of non-functionality
(direct outputs from the FEMA P-58 detailed results).
Quick Design Example
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• Final Design Outcomes:– Repair Cost: 2% [5-star]– Functional Recovery Time: 2 days [5-star]– Safety: Low fatality+injury risk and good egress) [5-star]
• This example was for new design, but FEMA P-58 offers this same level of building-specific detail when doing performance assessments as well.
Quick Design Example
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The FEMA P-58 method and SP3 are complete and ready for use. Even so, we are continuing further development to:
• Make the methods cover all structural systems and conditions (already covers nearly all of them).
• Streamline the analysis methods to make the analysis quicker.
Future Develop. in Resiliency/Risk Assessment
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Cover all structural systems:
Future Develop. in Resiliency/Risk Assessment
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Cover all structural systems:
Future Develop. in Resiliency/Risk Assessment
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Streamline analysis with the enhanced Statistical Response Method (to estimate structural responses without a complete structural model)
Future Develop. in Resiliency/Risk Assessment
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Streamline analysis with the enhanced Statistical Response Method (to estimate structural responses without a complete structural model)
Future Develop. in Resiliency/Risk Assessment
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Streamline analysis with the enhanced Statistical Response Method (to estimate structural responses without a complete structural model)
Future Develop. in Resiliency/Risk Assessment
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Further SP3 software development
Future Develop. in Resiliency/Risk Assessment
SP3 Engine
SP3-Engineering SP3-PML
SP3 Fragility Clearinghouse
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Questions and Discussion
Thank you for your time. Our goal is to support adoption of resilience-based design and risk
assessment, and we welcome feedback and suggestions.
Time for questions and discussion!
Curt Haselton: curt@hbrisk.com, (530) 514-8980 Jack Baker: jack@hbrisk.com
www.hbrisk.com