Opportunities for NEES Research Utilization

Robert D HansonProfessor Emeritus

University of Michigan

Who is responsible for adapting Who is responsible for adapting NEES research data?NEES research data?

• The NEES researchers are responsible

• Code committees and design professionals digest and adapt this data with active participation by researchers

• This is done by active participation in code committees and professional activities by researchers

How can this be enhanced? How can this be enhanced?

• NEES research proposals should include input and recommendations by the expected users

• NEES research efforts should included these professionals at the initiation, intermediate and concluding stages of the project

• These professionals can help disseminate the applicable results to the design community

Research Priorities – How are Research Priorities – How are they / should they be they / should they be

established? established? • NAE, EERI, BSSC, FEMA, NIST and material

groups have identified research needs• Each has a recommended priority – with

many listed at equal priority• A group of professionals and researchers

without a vested interest in a specific research agenda should create a priority list for use by NSF proposal review panel use

Two examples of NEES Research Two examples of NEES Research Opportunities – How these Opportunities – How these

projects identify priority needsprojects identify priority needs• ATC 58 – Performance-based Seismic

Design - Continuum of performance from small response [no damage], through various amounts of damage, to building collapse. Includes existing and new construction.

• ATC 63 – Quantification of Building System Performance and Response – For use in new building design requirements to prevent life-loss.

Major contributors to the Major contributors to the following are:following are:

• Mike Mahoney – DHS/FEMA• Ron Hamburger – ATC 58 Technical lead• Bob Bachman – ATC 58 NPP Lead• Craig Comartin - ATC 58 RMP Lead• Andrew Whittaker – ATC 58 SPP Lead• Eduardo Miranda - ATC 58 NPP team• Keith Porter – ATC 58 NPP team• Charles Kircher – ATC 63 Technical Lead

Building Code ProcessBuilding Code Process• Uses post-earthquake investigations, research

information, professional judgment, and observed construction problems

• Material standards are improved• NEHRP Recommended Provisions – Evaluation of

new systems and major increments in knowledge• ASCE 7 – References material standards and uses

input from NEHRP Recommendations as appropriate to update the current Standard

• IBC and NFPA adopt ASCE 7 with or without modifications

• Local and State Codes adopt IBC or NFPA with or without modifications

Building Code ProcessBuilding Code Process

Observation of poor performance

Performance-based designPerformance-based designA new approachA new approach

DoesPerformance

MeetObjectives?

No YesDoes

PerformanceMeet

Objectives?

No Yes

SelectPerformanceObjectives

DevelopPreliminary

Design

AssessPerformance

Capability

Done

ReviseDesign

First Generation ProceduresFirst Generation Procedures

• Federal Emergency Management Agency sponsored a series of development efforts focused on existing buildings:

• Evaluation guidelines Predict types of damage a building

would experience in future events

• Rehabilitation guidelines Procedures to design building

upgrades to achievedesired performance

SeismicEvaluation ofBuildings

ASCE-31

The First GenerationThe First Generation

Damage or Loss0% 100%

Time out of servicenone permanent

Joe’s

Beer!Beer!Food!Food!

Beer!Beer!Food!Food!

Joe’s

Operational LifeSafety

CollapsePrevention

Beer!Beer!Food!Food!

Joe’s

ImmediateOccupancy

Joe’s

Beer!Beer!Food!Food!

Joe’s

Beer!Beer!Food!Food!

Operational

Beer!Beer!Food!Food!

Joe’s

Beer!Beer!Food!Food!Beer!Beer!Food!Food!

Joe’s

LifeSafety

CollapsePrevention

Beer!Beer!Food!Food!

Joe’s

Beer!Beer!Food!Food!Beer!Beer!Food!Food!

Joe’sJoe’s

ImmediateOccupancy

PerformancePerformance

• The potential consequences of building response to earthquakes, including:Life loss and serious injury (Casualties)Direct economic loss (Cost = repair and

replacement costs)Indirect economic and social loss

(Downtime = loss of use of damaged or destroyed facilities)

Verifying Performance CapabilityVerifying Performance Capability

t

GroundMotion

StructuralResponse

Damage

Performance Metrics:Casualties, Cost & Downtime

All StepsRepresented On A

Probabilistic FrameworkConsidering Uncertainty

Example building assessment – Moehle’s EERI Lecture

Height

:

3 stories; 14 ft. floor to floor; 42 ft total

above grade; no

basement

Area

:

22,736 sq.ft. per

floor; 68,208 sq.ft.

total (actual building

slightly larger)

Occupancy

:

General office space

Performance assessment Performance assessment procedureprocedure

• Determine the hazard.

• Analyze the structure.

• Characterize the damage.

• Compute the losses.

Performance group fragilities for Performance group fragilities for Damage States 1, 2 and 3Damage States 1, 2 and 3

Fragility curves for direct loss calculations

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 2 4 6 8

Story drift (% of story height)

P (

DS

> D

Si)

DS1

DS2

DS3

Example design decisionsExample design decisions

4%

4%

5%

8%

12%

25%

41%

0% 5% 10% 15% 20% 25% 30% 35% 40% 45%

Roof top equipment

Structure

Contents (Ist and 2nd flr. offices)

Interior nonstructural (accel. sensitive)

Interior nonstructural (drift sensitive)

Contents (3rd flr. computer center)

Exterior envelope

Portion of annualized capital loss

Performance group fragility functionsPerformance group fragility functions

Fragility Functions

Structural Response Parameters

(Engrg. Demand Parameters)

Structural and Nonstructural Damage

• In order to establish fragilities it is necessary to establish a relationship between the building response and its associated damage

(Probabilistic Mapping Functions)

Performance group fragility functionsPerformance group fragility functions

INCREASING INTERSTORY DRIFT

DM1

First Visible Damage

DM2

Wide cracks

DM3

Punching failure

DM4

Loss of vertical carrying capacity

What Data is Needed? What Data is Needed? Protocol for data reportingProtocol for data reporting

1. Description of the specimen(s)

(Example based on research by Arnold, Uang and Filiatrault, 2002)

What Data is Needed? What Data is Needed? Protocol for data reportingProtocol for data reporting

2. Description of the loading

(Example based on research by Arnold, Uang and Filiatrault, 2002)

What Data is Needed? What Data is Needed? Protocol for data reportingProtocol for data reporting

3. Detailed description of observed damage at each loading level

(Example based on research by Arnold, Uang and Filiatrault, 2002)

IDR=0.34%

What Data is Needed? What Data is Needed? Protocol for data reportingProtocol for data reporting

(Example based on research by Arnold, Uang and Filiatrault, 2002)

IDR=0.40%

3. Detailed description of observed damage at each loading level

Interim Loading Protocols Interim Loading Protocols

• FEMA 461 – Interim Protocols for Determining Seismic Performance Characteristics of Structural and Nonstructural Components Through Laboratory Testing – provides protocols for quasi-static cyclic testing of components and shake table testing of acceleration sensitive components

How will the data be used to How will the data be used to generate fragilities?generate fragilities?

• Method A – all specimens failed at observed test levels

• Method B – only some specimens failed

• Method C – no specimens failed [qualification tests]

• Method D – analytically derived fragilities without tests

• Method E – expert opinion without test data

• Method U – updating existing fragilities using new failure data or post-earthquake investigations

Six methods are proposed depending upon the data

How will the data be used to How will the data be used to generate fragilities?generate fragilities?

Gypsum Wall Partition

0.0

0.2

0.4

0.6

0.8

1.0

0.000 0.005 0.010 0.015 0.020 0.025 0.030 0.035 0.040

Interstory Drift Ratio

P( DS | IDR )

DS1 Data DS2 Data DS3 Data Lognormal Fit DS1 Lognormal Fit DS2 Lognormal Fit DS3

Gypsum Wall Partition

0.0

0.2

0.4

0.6

0.8

1.0

0.000 0.005 0.010 0.015 0.020 0.025 0.030 0.035 0.040

Interstory Drift Ratio

P( DS | IDR )

DS1 Data DS2 Data DS3 Data Lognormal Fit DS1 Lognormal Fit DS2 Lognormal Fit DS3

How will the data be used to How will the data be used to generate fragilities?generate fragilities?

ATC 63 – Building Performance ATC 63 – Building Performance to Collapse to Collapse

current statuscurrent status

• Planar analytical response of reinforced concrete moment frames, reinforced concrete shear wall buildings, timber townhouse and apartment buildings, autoclaved aerated concrete buildings, and steel moment frame buildings

• Ibarra-Krawinkler degrading hysteresis model used for component behavior

ATC 63 – Building Performance ATC 63 – Building Performance to Collapse to Collapse

• Biaxial experimental data not available to perform 3-D dynamic response analyses

• Limited full-scale building test data available for system performance calibration of analyses

• Limited reduced-size building systems test data available

• Very limited experimental data available to system collapse levels of deformation

Building Performance Building Performance What can NEESR provide?What can NEESR provide?

• Sufficient archived data at all damage levels from no damage, through various damage states, to collapse. Include displacement-damage relationships and likely repairs needed for each level.

• Multiple tests of similar specimens to establish reliability coefficients for the data.

• Data on nonstructural components

• Data on structural components

• Data on systems of components

More information on projects More information on projects and participation opportunities and participation opportunities

available atavailable at

www.atcouncil.org