Recovery Modelling of Buildings Post-Earthquake

1. Aim

The aim of this study is to investigate post-earthquake recovery timelines of buildings by analyzing structural damage, functional impediments, and regional factors affecting recovery. The study focuses on understanding the difference between repair and recovery, quantifying impedance factors, and evaluating recovery behavior across different building typologies using seismic resilience frameworks such as FEMA P-58 and REDi.

2. Introduction

Earthquakes not only cause structural damage but also disrupt the functionality of buildings for extended durations. Traditional seismic design focuses on life safety; however, modern approaches emphasize functional recovery and resilience.

Recovery of buildings depends on:

Structural damage levels

Non-structural damage

External impedances such as permits, financing, and contractor availability

This study explores how buildings transition from damage → repair → recovery, highlighting that recovery is a system-level problem involving engineering, governance, and socio-economic factors.

3. Literature Survey and Technologies Used

FEMA P-58 Framework

A performance-based methodology for assessing seismic performance.

Evaluates consequences such as:

Casualties

Repair costs

Repair time

Based on the PEER probabilistic framework.

Moves beyond prescriptive design to simulate real building performance.

REDi Framework (2013, Arup)

Focuses on functional recovery instead of just survival.

Defines resilience levels:

Silver (Re-occupancy)

Gold (Functional Recovery)

Platinum (Enhanced Recovery)

Key contribution: Impedance Factors

Inspection delays

Permits

Financing

Contractor mobilization

Material procurement

Redesign and coordination

These factors significantly extend recovery timelines even when structural damage is minor.

Case Studies Reviewed

2015 Gorkha Earthquake

1999 Izmit Earthquake

2006 Yogyakarta Earthquake

2011 Christchurch Earthquake

2014 Napa Valley Earthquake

2023 Turkey Earthquake

Key Observations

Poor construction → high structural damage (Gorkha, Turkey)

Strong codes → low casualties but high downtime (Napa, Christchurch)

Liquefaction caused major failures (Christchurch)

Financial and governance systems strongly influence recovery

4. Methodology

The methodology involved a combination of theoretical study, case analysis, and deterministic modeling:

Step 1: Literature Review

Study of seismic engineering fundamentals

Review of FEMA P-58 and REDi frameworks

Analysis of reconnaissance reports and journal papers

Step 2: Case Study Analysis

Evaluation of damage, losses, and recovery across multiple earthquakes

Identification of:

Structural performance

Financial losses

Impedance factors

Casualties

Step 3: Building Typology Selection

RC Moment Frames

RC with Masonry Infills

Steel Moment Frames

Step 4: Recovery Timeline Modelling

Damage states considered:

Slight

Moderate

Extensive

Complete

Total Recovery Time calculated as:
Recovery Time = Repair Time + Impedance Delays

Impedance factors included:

Inspection

Permitting

Financing

Contractor mobilization

Material procurement

Redesign

Coordination

Repair times taken from HAZUS, impedance values estimated based on reports.

Step 5: Excel-Based Framework

Developed a deterministic model to quantify recovery timelines across regions and typologies.

5. Results

General Findings

Impedance delays dominate recovery timelines

Recovery time increases significantly with damage severity

Repair time is only about 1/3rd of total recovery time

Typology-Based Observations:

RC Moment Frames

Slight damage → repaired within ~2 weeks

Severe damage → long delays due to redesign and approvals

Faster recovery in developed regions (insurance + systems)

RC with Masonry Infills

Moderate damage requires engineer verification

Extensive damage leads to major delays due to approvals and funding

Rural areas show significantly slower recovery

Steel Moment Frames

Faster recovery potential due to:

Prefabrication

Ductility

Delays in developing countries due to:

Weak supply chains

Lack of expertise

Regional Observations:

Developed countries (USA, NZ):

Faster inspections

Insurance-driven recovery

Strong contractor networks

Developing countries (India, Nepal, Turkey):

Delays in permits and funding

Lack of skilled contractors

Poor coordination systems

Key Insight: Repair vs Recovery

Repair = fixing physical damage

Recovery = restoring full functionality

Recovery is delayed by:

Utility restoration

Permits

Coordination

Social and psychological factors

6. Conclusions / Future Scope

Conclusions

System failure (governance, logistics) impacts recovery more than structural damage

Existing frameworks (REDi, HAZUS) are not fully applicable to developing countries

Recovery depends heavily on building function (hospitals prioritized)

Social and psychological readiness also influence recovery

Resilience requires integration of:

Engineering

Policy

Governance

Community preparedness

Future Scope

Develop region-specific recovery models for India

Incorporate probabilistic modeling of impedance factors

Improve post-disaster governance frameworks

Integrate resilience planning into building codes

Expand dataset using real-time post-earthquake data

7. Appendix:

APPENDIX A1-  2015 Gorkha earthquake

APPENDIX A2-  2006 Yogyakarta earthquake

APPENDIX A3-  1999 Izmit earthquake

APPENDIX B-  EXCEL REPORT

APPENDIX C-  RECOVERY TIMELINE

8. References:

a.https://ssc.ca.gov/wp-content/uploads/sites/9/2020/08/gem_back_to_normal.pdf

b.https://www.michelbruneau.com/DISTRIBUTION-COPY-of-Reconstruction-of-Christchurch-in-Steel-Nov-2017-2.pdf

c.https://www.researchgate.net/publication/342436429_The_seismic_performance_of_structural_steel_buildings_in_the_20102011_Christchurch_Earthquake_series_and_the_2016_Kaikoura_earthquake_lessons_learned_ongoing_research_and_needs_of_industry

dhttps://www.newsteelconstruction.com/wp/shaken-and-stirred.

e.https://scnz.org/structural-steel-dominates-christchurch-rebuild

f.https://www.gfdrr.org/sites/default/files/publication/Engaging%20Local%20Actors%20in%20Disaster%20Recovery%20Frameworks%20-%20Final.pdf

g.https://recovery.preventionweb.net/publication/housing-reconstruction-post-earthquake-gujarat-comparative-analysis

h.https://www.slideshare.net/slideshow/gorkha-earthquake-recovery-challenges-in-a-fluid-terrain/88663073

i.https://link.springer.com/article/10.1186/s40623-016-0483-4

j.https://www.sciencedirect.com/science/article/abs/pii/S2212420920303332

k.https://www.fema.gov/sites/default/files/documents/fema_hazus-earthquake-model-technical-manual-6-1.pdf

l.https://www.usrc.org/wp-content/uploads/REDi_Final-Version-1.0_October-2013.pdf

Mentors: Prakhyath V Shetty, Muskan Kumari Singh, Asiya Fathim

Mentee: Dhanush Naidu