SEISMIC ASSESMENT of SAN JUAN DE DIOS HOSPITAL using FRAGILITY CURVES ENGR. MICHAEL B. BAYLON HERMAN D. CARANTO, ARJOHN P. ESPINO ,JOSEPH BRYAN NILO CIVIL ENGINEERING DEPARTMENT ADAMSON UNIVERSITY

INTRODUCTION Hospitals play an important role in the health care system of the country Having been built in the 1950’s, the structure is expected to be susceptible to large magnitude earthquakes an unpredictable movement of the West Valley Fault System will cause substantial damage throughout Metro Manila

Seismic Fragility Analysis analysis of the probability that a structural system violates at least a limit state when subjected to a seismic event of specified intensity best way to accomplish vulnerability assessments of structures for judging the seismic requirements

Seismic Fragility Curves output of seismic fragility analysis plots the percentage probability of exceeding a particular damage state vs. ground motion intensity (GMI)

Objectives of the Study

Main Objective Specific Objectives To develop sets of fragility curves for various damage states for a specific building. Specific Objectives 1.To provide a seismic assessment of the San Juan de Dios Hospital against large- magnitude earthquakes 2.To provide a static and dynamic analysis of the building against earthquake loads using Pushover Analysis and Time History Analysis 3.To justify the structural design of the structure using the obtained fragility curves

Conceptual Framework

Conceptual Framework Input Process Output Ground Motion Data Structural Plan of San Juan de Dios Hospital Process Model of structure using SAP2000 Pushover Analysis and Time History Analysis using Sap 2000 Output Damage Rank and Damage Index Seismic Fragility Curves Evaluation of the obtained fragility curves

Scope and Limitations of the Study Use of two analyses Non-linear Static Analysis (Push- over Analysis) and the Non-linear Dynamic Analysis (Time History Analysis) using the SAP2000 structural engineering software shear as the mode of failure Karim & Yamazaki (2004), Shinozuka (2000), Requiso, Balili, & Garciano (2013), Baylon (2017).

Scope and Limitations of the Study ground motion data from four recorded earthquakes will be used for the analysis (1) Mindoro Station-Philippines 1995, Magnitude 7.1 (2) Kobe-Japan 1995, Magnitude 6.9 (3) Tohoku-Kanto-Japan 2011, Magnitude 9.0 (4) Bohol-Philippines 2013, Magnitude 7.2

Methodology

Research Design

Structural Model Ground Motion Data Mode of Failure SHEAR Nonlinear Dynamic Analysis (Time History Analysis) Nonlinear Static Analysis (Pushover Analysis) Parameters For Damage Index Damage Indices Seismic Fragility Curves

DAMAGE INDEX DUCTILITY FACTORS PARAMETERS NUMBER OF OCCURENCE DI DAMAGE INDEX DUCTILITY FACTORS PARAMETERS NUMBER OF OCCURENCE PROBABILITY OF EXCEEDANCE SEISMIC FRAGILITY CURVE DAMAGE RANK

RESULTS AND DISCUSSION

Three-Dimensional Model of San Juan de Dios Hospital

Pushover Analysis

PUSHOVER CURVES Y- Direction

PUSHOVER CURVES Y- Direction

PUSHOVER CURVES X- Direction

PUSHOVER CURVES X- Direction

Discussion of Results Y- direction is able to withstand a maximum shear force of 1996.3 kN with 0.02023 m displacement X- direction which can tolerate 4356 kN with 0.011 m displacement weak axis is y, strong axis is x

Time History Analysis

HYSTERETIC CURVES 0.2g Bohol X 0.2g Bohol Y

HYSTERETIC CURVES 0.4g Bohol X 0.4g Bohol Y

HYSTERETIC CURVES 0.6g Bohol X 0.6g Bohol Y

HYSTERETIC CURVES 0.8g Bohol X 0.8g Bohol Y

HYSTERETIC CURVES 1.0g Bohol X 1.0g Bohol Y

HYSTERETIC CURVES 1.2g Bohol X 1.2g Bohol Y

HYSTERETIC CURVES 1.4g Bohol X 1.4g Bohol Y

HYSTERETIC CURVES 1.6g Bohol X 1.6g Bohol Y

HYSTERETIC CURVES 1.8g Bohol X 1.8g Bohol Y

HYSTERETIC CURVES 2.0g Bohol X 2.0g Bohol Y

Elapsed Time to Complete a Analysis

Area Computation of Hysteretic Energy

Excel Spreadsheet for Computing the Parameters

Fragility Curve X Determinant PGA Slight Damage Moderate Extensive Complete Damage BOHOL 2013 0.22g (Magnitude 7.2)   14% 10% 4% 2% KOBE 1995 0.82g (Magnitude 6.9) 69% 66% 53% 40%

Fragility Curve Y Determinant PGA Slight Damage Moderate Damage Extensive Complete BOHOL 2013 0.22g (Magnitude 7.2)   25% 8% 3% 2% KOBE 1995 0.82g (Magnitude 6.9) 75% 62% 46% 38%

Probability of Exceedance Vs. PGA as the peak ground acceleration increases, the probability of exceedance for every damage states also increases as for this structure

Summary of Results for X-Direction Determinant PGA Slight Damage Moderate Extensive Complete Damage MINDORO 1999 0.15g (Magnitude 5.0)   5% 3% 1% 0% BOHOL 2013 0.22g (Magnitude 7.2) 14% 10% 4% 2% DESIGN PGA-2010 NSCP 0.4g 37% 32% 18% KOBE 1995 0.82g (Magnitude 6.9) 69% 66% 53% 40% TOHOKU-KANTO 2011 2.99g (Magnitude 9.0) 100%

Summary of Results for Y-Direction Determinant PGA Slight Damage Moderate Damage Extensive Complete MINDORO 1999 0.15g (Magnitude 5.0)   10% 3% 0% BOHOL 2013 0.22g (Magnitude 7.2) 25% 8% 2% DESIGN PGA-2010 NSCP 0.4g 49% 27% 13% KOBE 1995 0.82g (Magnitude 6.9) 75% 62% 46% 38% TOHOKU-KANTO 2011 2.99g (Magnitude 9.0) 100%

Summary of Results for Design 0.4g PGA the structure is prone to slight damage at 37% for the x-direction and 49% for the y-direction while moderate damage falls at 32% for the x-direction and 27% for the y-direction. Extensive damage and complete damage index have about 10% probability

Conclusion The structure does not meets the 0.4g peak ground acceleration minimum requirement of the 2010 NSCP Building Code a structure with a 30 or more years of lifespan is NOT SAFE when subjected to a seismic event of 10% probability of exceedance of collapse of total damage. The structure being more than 50 years old is vulnerable to large magnitude earthquakes

Conclusion

Conclusion

Recommendation use of another software such as ETABS for modeling of the structure and performing nonlinear static and dynamic analysis use drift as mode of failure as an addition use period of ground motion as abscissa in plotting the fragilty curves instead of the intensity use of other methods for computation of fragility curves such as Monte Carlo Simulation and Response Surface Method

Acknowledgment Dr. Lessandro Estelito O. Garciano Dr. Andres Winston C Acknowledgment Dr. Lessandro Estelito O. Garciano Dr. Andres Winston C. Oreta research/thesis adviser research mentors from De La Salle University – Manila

Thank you for listening! ikingbalon@gmail.com michael.baylon@adamson.edu.ph https://www.researchgate.net/home