Disaster Mitigationin Health Facilities:

Wind EffectsNonstructural Issues

Disaster Mitigationin Health Facilities:

Wind EffectsNonstructural Issues

22

Nonstructural elements to consider Nonstructural elements to consider when assessing vulnerabilitywhen assessing vulnerabilityNonstructural elements to consider Nonstructural elements to consider when assessing vulnerabilitywhen assessing vulnerability

•Façades•Roof covers•Parapets•Chimneys•Plaster•Glass windows•Attachments (signs, antennae,etc)

•Ornaments•Canopies•Railings•Doors and exit routes

•Medical equipment•Industrial equipment

•Supplies•Office equipment

•Medical and industrial gases

•Air conditioning•Electrical generator•Hydraulic networks•Electric networks

ARCHITECTURAL EQUIPMENT BASIC INSTALLATIONS

33

• Previous experiencePrevious experience• Visual inspectionVisual inspection• Data collectionData collection• Non-destructive testsNon-destructive tests• Mathematical modelsMathematical models• Structural analysis and designStructural analysis and design• Wind tunnel analysisWind tunnel analysis• Retrofitting recommendationsRetrofitting recommendations• EqEquipment classificationuipment classification

Nonstructural vulnerability Nonstructural vulnerability assessment methodsassessment methodsNonstructural vulnerability Nonstructural vulnerability assessment methodsassessment methods

44

Standards and codes must Standards and codes must cover components and cover components and claddingscladdings

The trend for international standards The trend for international standards is to adopt and adapt the ASCE-7 is to adopt and adapt the ASCE-7 approach for components and approach for components and claddings.claddings.

55

Design pressure for components and Design pressure for components and cladding and design force for special cladding and design force for special and open structures (ASCE-7)and open structures (ASCE-7)

Towers, signs, tanks, Towers, signs, tanks, silossilos

p = qh [(GCp) - (GCpi)]

F = qzGCf Af

Design pressureDesign pressure

Design forceDesign force

66

Indispensable: Equipment that can not easily or economically be

replaced and is essential for the provision of

health services.

Essential: Similar to indispensable equipment, except that

it can be replaced easily or

cheaply.

Hazardous: Equipment that can injure people and

damage objects.

Chaotic: Equipment whose failure may cause disruption

to its environs.

Functional: Equipment that is not used for emergency

health care.

Criteria for equipment Criteria for equipment classificationclassificationCriteria for equipment Criteria for equipment classificationclassification

77

Hipped roof recommended Hipped roof recommended over flat roofover flat roofHipped roof recommended Hipped roof recommended over flat roofover flat roof

88

Gabled roof with slopes of Gabled roof with slopes of 20 to 30 degrees are 20 to 30 degrees are preferred against hurricanespreferred against hurricanes

Gabled roof with slopes of Gabled roof with slopes of 20 to 30 degrees are 20 to 30 degrees are preferred against hurricanespreferred against hurricanes

PLAN ISOMETRIC

Hatched area indicateswhere more frequent

fixings are required

Gabled roof

99

Connection details between Connection details between metal sheet roof and purlinsmetal sheet roof and purlins

Metal sheet fixings andpurlin-to-rafter connection

Spacer block

Self-tapping screw

Metal sheeting

purlin

Galvanized hurricane strapfixed to rafter and purlin

Rafter

Ridge connection

Valley connection

1010

Typical connection system Typical connection system between metal sheet roof and between metal sheet roof and masonry wallmasonry wall

Typical connection system Typical connection system between metal sheet roof and between metal sheet roof and masonry wallmasonry wall

1111

Nonstructural elementsNonstructural elementsare not designed to resist are not designed to resist direct loadsdirect loads

Failure of an unreinforced Failure of an unreinforced masonry wall without an masonry wall without an adequate base anchorageadequate base anchorage

Failure of an unreinforced Failure of an unreinforced masonry wall without an masonry wall without an adequate base anchorageadequate base anchorage

1212

Shutters protect against Shutters protect against the penetration of flying the penetration of flying objects and waterobjects and water

1313

For a hospital it is essential to have For a hospital it is essential to have protection against penetration of protection against penetration of windborne debris and waterwindborne debris and water

1414

Anchorage of protective shutters Anchorage of protective shutters on outside wallson outside walls

1515

Anchorage system of shutters Anchorage system of shutters on interior columnson interior columns

1616

Exterior doors must be protected Exterior doors must be protected against internal and external pressures against internal and external pressures through adequate anchoragesthrough adequate anchorages

1717

Window deformations due to Window deformations due to the impact of windborne the impact of windborne debrisdebris

1818

Impact of windborne debris against Impact of windborne debris against louvre windowslouvre windows

1919

An unprotected window is An unprotected window is vulnerable in the event of a vulnerable in the event of a hurricanehurricane

2020

Roll-up or permanent shutters are Roll-up or permanent shutters are the best way to protect windows the best way to protect windows against hurricanesagainst hurricanes

2121

Permanent window shutter detailsPermanent window shutter details

ELEVATION

Storm shutter in open position

when closedSurface bolts to secure

PLAN

fixed to frameShutter panels

2222

Housing chamber for

ELEVATION

CROSS SECTION

Shutter guide

roll-up shutter

Details of roll-up Details of roll-up shuttershutter

2323

Adequate anchorage of hospital Adequate anchorage of hospital equipment will ensure equipment will ensure continuous servicecontinuous service

2424

An example of good An example of good anchorage on exterior anchorage on exterior hospital equipmenthospital equipment

2525

Exterior equipment should be Exterior equipment should be anchored with special bandsanchored with special bands

2626

External oxygen and gas External oxygen and gas tanks should not be loosetanks should not be loose

2727

Correct anchorage of external Correct anchorage of external oxygen and gas tanks to wallsoxygen and gas tanks to walls

2828

Restraints and fasteners Restraints and fasteners for larger external for larger external equipmentequipment

Restraints and fasteners Restraints and fasteners for larger external for larger external equipmentequipment

2929

Failure of a metallic roof cover Failure of a metallic roof cover and an unreinforced masonry and an unreinforced masonry wallwall

3030

Metal sheet roof of a health center Metal sheet roof of a health center was destroyed by hurricane-force was destroyed by hurricane-force windswinds

3131

Damage to the faDamage to the faççade due to ade due to failure of a neighboring buildingfailure of a neighboring building

3232

A roof from a structure A roof from a structure located 100 m away was located 100 m away was violently thrown by the violently thrown by the strong winds of a hurricanestrong winds of a hurricane

Windborne debris on a Windborne debris on a structurestructure

3333

Impact of windborne debris on a Impact of windborne debris on a plywood hurricane shutterplywood hurricane shutter

3434

Windborne debris perforates Windborne debris perforates shutter and glass behind itshutter and glass behind it

3535

Health center damaged by a water Health center damaged by a water tank thrown by hurricane windstank thrown by hurricane winds

Pan American Health Organization, 2005

These slides have been made possible through the financial support of the Disaster Preparedness Program of the Humanitarian Aid Office, ECHO (DIPECHO-III)

Ph: (809) 567-9271Fax: (809) 566-3200danielc@intec.edu.dowww.intec.edu.do

Grupo de Estabilidad Estructural (Ge2) / INTECAve Los Próceres, GaláApdo 349-2Santo Domingo, Dominican Republic