Engineering Approaches to Disaster Risk Reduction and Management “Resilience of Structures” Presented by Prof. Fernando J. Germar (UP Diliman) 2019 ProSPER.Net Leadership Programme 24-30 November, 2019

1. Engineering Approaches to Disaster
Risk Reduction and Management
“Resilience of Structures”
Fernando J. Germar, Ph.D.
Director, UP Building Research Service
Professor, UP Institute of Civil Engineering

2. Presentation Outline
• Definition of Terms
• Addressing Resilience in Design and
Construction
• Hazard Maps
• Seismic Structural Resilience
• Improving Seismic Resilience

3. Definition of Terms
• Hazard, Vulnerability, Risk
• Examples of engineering hazards
– Earthquakes
– Strong winds
– Fire
– Flooding, Tsunami, Storm Surge
– Landslides
– Volcanic eruption

4. Definitions
• Resilience – “The ability of a system, community
or society to resist, absorb, accommodate to and
recover from the effects of a hazard in a timely
and efficient manner, including through the
preservation and restoration of its essential basic
structures and functions” (UNISDR, 2009)
• Resilience – ability to survive the application of a
force by resisting it with strength (rigidity or
stiffness) and absorbing it with determination
(ductility)

5. Addressing Resilience in Design and
Construction of Structures
Japan
• Building Standards Law
2005
– Enforcement Regulation
– Enforcement Order (Technical
Requirements)
– Administration by Local
Jurisdictions
• Fire Service Law
New Zealand
• Building Act 2004
– Building Regulations
– Building Code (Building
Standards)
– Administration by Local
Jurisdictions
• Fire and Emergency New
Zealand Act 2017

6. Addressing Resilience in Design and
Construction of Structures
• National Building Code of the Philippines
(Presidential Decree 1096) – a law containing
administrative and legal provisions as well as
technical standards
– Implementing Rules and Regulations
• Referral Codes: National Structural Code of the
Philippines, Philippine Electrical Code, Philippine
Mechanical Code, National Plumbing Code of the
Philippines, etc.
– Implementation by Local Jurisdiction

7. General Design Objectives
Stability : to prevent overturning, sliding, or
buckling of the structure, or parts of it, under the
action of loads
Strength: to resist safely the stresses induced by the
loads in the various structural members
Serviceability: to ensure satisfactory performance
under service load conditions: providing adequate
stiffness and reinforcements to contain deflections,
crack-widths and vibrations within acceptable
limits; providing impermeability and durability
(including corrosion resistance), etc.

8. HAZARD MAPS

9. Philippine Earthquake Hazard Map

10. Philippine Wind Zone Map
• 2015 Revision (3 second
gust wind)
– 15% Probability of
Exceedence in 50 years
– 7% Probability of
Exceedence in 50 years
– 3% Probability of
Exceedence in 50 years
2010
NSCP

11. Hazards Map
How about tsunami? Or storm surge?
Or liquefaction?
How about flooding? Or landslides?
There’s still a need for hazards map at the national
level and local level

12. Securing Permits for Construction
LOCATIONAL
CLEARANCE
BUILDING PERMIT
OCCUPANCY PERMIT
COMPREHENSIVE
LAND USE PLAN

13. Comprehensive Land Use Plan
• Base Zones
– Residential, Commercial, Industrial, Agricultural,…
• Overlay Zones
– Flood Overlay Zone
– Landslide Overlay Zone
– Historical or Heritage Overlay Zone
– Protection and Conservation Overlay Zone
– No Build Zone

14. Flood Hazard Map

15. Liquefaction Potential Map of Metro
Manila
Source: AIR Philippines

16. Tsunami Prone Areas in the Philippines

17. SEISMIC STRUCTURAL RESILIENCE

18. Earthquake Hazard Levels
Probability MRI Frequency
50%-50 year 72 years Frequent
20%-50 year 225 years Occasional
10%-50 year (BSE-1) 474 years Rare
2%-50 year* (BSE-2) 2475 years Very rare
*2003 NEHRP Recommended Provisions
maximum considered earthquake.

19. Seismic Design Philosophy
Under minor but frequent shaking,
• main members of the buildings that carry
vertical and horizontal forces should not be
damaged
• Building parts that do not carry load may
sustain repairable damage
• Building will be fully operational within a short
period and repair costs will be small

20. Seismic Design Philosophy
Under moderate but occasional shaking
• Main members may sustain repairable
damage
• Other parts of the buildings may be damaged
such that they may even have to be replaced
after the earthquake
• Building will be operational once the repair
and strengthening of the damaged main
members is completed

21. Seismic Design Philosophy
Under strong but rare shaking
• Main members may sustain severe (even
irreparable damage but the building should
not collapse

22. Performance Objectives

23. Performance Objectives

24. National Structural Code of the
Philippines (NSCP) Classifications
Occupancy Category I (Essential Facilities)
• Public School Buildings
• Hospitals
• Occupancies having surgery and emergency
treatment areas
• Fire and Police Stations
• Designated Evacuation Centers

25. National Structural Code of the
Philippines (NSCP) Classifications
Occupancy Category I (Essential Facilities) cont.
• Garages and shelters for emergency vehicles and
emergency aircraft
• Structures and shelters in emergency
preparedness centers
• Structures and equipment in communications
centers and other facilities required for
emergency response

26. National Structural Code of the
Philippines (NSCP) Classifications
Occupancy Category I (Essential Facilities) cont.
• Aviation control towers
• Facilities for standby power-generating
equipment for Category 1 structures
• Tanks or other structures containing, housing or
supporting water or other fire-suppression
materials or equipment
• Power and communication transmission lines

28. Improving Structure Resilience
• Proper location of structure
• Designing for identified hazards
• Proper building code administration and
implementation
• Retrofitting of old vulnerable structures
✭ Proposed Philippine Building Act of 2019

29. MARAMING SALAMAT PO!