earthquake engineering 2011 lec-01
DESCRIPTION
First Lecture of Sunday 12-03-2011by : tharwat SakrTRANSCRIPT
EARTHQUAKEEARTHQUAKEEARTHQUAKEEARTHQUAKEENGINEERINGENGINEERING
11..11. Introduction. Introduction
11..11..11. Definitions. Definitions
11..11..22. Earthquake Hazards. Earthquake Hazards
11..11..33. Course Layout. Course Layout
1.1.1. DEFINITIONS
Earthquake EngineeringEarthquake Engineering■■ Earthquake EngineeringEarthquake Engineering■■• can be defined as the branch of engineering devoted to mitigating
earthquake hazards. In this broad sense, earthquake engineeringh i i i d l i f h bl d bcovers the investigation and solution of the problems created by
damaging earthquakes, and consequently the work involved in thepractical application of these solutions, i.e. in planning, designing,constructing and managing earthquake resistant structures andconstructing and managing earthquake‐resistant structures andfacilities.
ScopeScope■■ ScopeScope■■• Seismicity ,Nature, Measures and Recording of earthquakes.• Planning for Seismic Risk Assessment & MitigationPlanning for Seismic Risk Assessment & Mitigation• Analysis, Design and Construction of Earthquake Resistant Structures• Evaluation of Buildings for Earthquake Resistance
R t fitti f E th k d d St t• Retrofitting of Earthquake damaged Structures• Earthquake Management and Security
1.1.1. DEFINITIONS
An EarthquakeAn Earthquake■■• is the motion or vibration, sometimes violent, of the earth’s surface that follows
a release of energy in the earth’s crust. This energy can be generated by a sudden dislocation of segments of the crust by a volcanic eruption or even by
An Earthquake An Earthquake ■■
sudden dislocation of segments of the crust, by a volcanic eruption, or even by manmade explosions.
Sources of Ground MovementsSources of Ground Movements■■• Tectonic Earthquakes
l• Volcanoes• Explosions• Collapse of Mines & Large Reservoirs• Tsunami
1.1.2. EARTHQUAKE HAZARDS
Failure of SlopesFailure of Slopes■■ Failure of SlopesFailure of Slopes
1.1.2. EARTHQUAKE HAZARDS
Occurrence of FireOccurrence of Fire■■ Occurrence of FireOccurrence of Fire
1.1.2. EARTHQUAKE HAZARDS
Building CollapseBuilding Collapse■■ Building CollapseBuilding Collapse
1.1.2. EARTHQUAKE HAZARDS
Building CollapseBuilding Collapse■■ Building CollapseBuilding Collapse
1.1.2. EARTHQUAKE HAZARDS
Building CollapseBuilding Collapse■■ Building CollapseBuilding Collapse
1.1.2. EARTHQUAKE HAZARDS
Bridge CollapseBridge Collapse■■ Bridge CollapseBridge Collapse
1.1.2. EARTHQUAKE HAZARDS
Land SlideLand Slide■■ Land SlideLand Slide
1.1.2. EARTHQUAKE HAZARDS
■■ DisturbanceDisturbance
1.1.2. EARTHQUAKE HAZARDS
■■ Specific FailuresSpecific Failures■■ Specific FailuresSpecific Failures
•
Collapse of the first storey and damageCollapse of the first storey and damage due to pounding between adjacent buildings during the Kocaeli earthquake, Turkey, August 17, 1999, Magnitude 7 4
Collapse of a high-rise building because of failure of the columns at the first storey d i th Chi Chi th k T i Magnitude 7.4 during the Chi-Chi earthquake, Taiwan, September 20, 1999, Magnitude 7.6
1.1.2. EARTHQUAKE HAZARDS
May May 2008 2008 China EarthquakeChina Earthquakeyy qqDate : May 12, 2008, 14:28
Magnitude : 8 0 Richter Scale Earthquake
Location : Sichuan, China
Magnitude : 8.0 Richter Scale Earthquake
Death : 69,016
Missing :18,627
Displaced :15 006 341
Injured : 373,573
Displaced :15,006,341
School Destroyed : 6,898
Rescue workers : 130,000
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.1.2. EARTHQUAKE HAZARDS
4 5M h d d4.5M homes destroyed
Some counties completely wiped off the mapwiped off the map
More than 11M people Displaced At this momentAt this moment
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.1.2. EARTHQUAKE HAZARDS
Thousands of tents are needed
Food and water are needed
Medical supplies are neededMedical supplies are needed
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.1.3. COURSE LAYOUT
1 1 ■■ IntroductionIntroduction
2 2 ■■ Seismicity : Nature, Measures and Characteristics of Seismicity : Nature, Measures and Characteristics of Earthquakes Earthquakes
33■■ Methods of Earthquake Analysis of StructuresMethods of Earthquake Analysis of StructuresTime HistoryTime HistoryyyResponse SpectrumResponse SpectrumEquivalent Static LoadsEquivalent Static Loads
According to the Egyptian Code According to the Egyptian Code –– UBC UBC -- IBCIBC
44■■ Earthquake Design of StructuresEarthquake Design of Structures
55 P ti l d A hit t l C id tiP ti l d A hit t l C id ti55■■ Practical and Architectural ConsiderationsPractical and Architectural Considerations
EARTHQUAKEEARTHQUAKE
N f N f
EARTHQUAKEEARTHQUAKEENGINEERINGENGINEERING
11..22. Nature of . Nature of EarthquakesEarthquakes
11..22..11. Causes of Earthquakes. Causes of Earthquakes
11..22..22. Faults. Faults
11..22..33. Earthquake Effects. Earthquake Effects
1.2.1. Causes of Earthquakes
Tectonic EarthquakesTectonic Earthquakesare caused by the sudden dislocation of large rock masses alonggeological faultsfaults within the earth's crust. The Earth is formed of
l l h h diff h i l d h i l
Tectonic EarthquakesTectonic Earthquakes
several layers that have very different physical and chemicalproperties. The outer layer, which averages about 70 kilometersin thickness, consists of about a dozen large, irregularly shapedplates that slide over under and past each other on top of theplates that slide over, under and past each other on top of thepartly molten inner layer . MostMost earthquakesearthquakes occuroccur atat thetheboundariesboundaries wherewhere thethe platesplates meetmeet ..
Plate Tectonic InteractionsFlash movie
Dr. Osman Shalan Dr. Tharwat Sakr
1.2.1. Causes of Earthquakes
Volcanic EarthquakesVolcanic Earthquakes
Earthquakes that can bereasonably associated with
Volcanic EarthquakesVolcanic Earthquakes
reasonably associated withvolcanoes are relatively rareand fall into three categories:
(i) volcanic explosions,
(ii) shallow earthquakes from(ii) shallow earthquakes frommagma movements, and
(iii) sympathetic tectonic(iii) sympathetic tectonicearthquakes
Dr. Osman Shalan Dr. Tharwat Sakr
1.2.1. Causes of Earthquakes
ExplosionsExplosions
Earthquakes may be produced
ExplosionsExplosions
q y pby the undergrounddetonation of chemical ornuclear devices When anuclear devices. When anuclear device is detonated ina borehole underground,enormous nuclear energy isreleased .
Dr. Osman Shalan Dr. Tharwat Sakr
1.2.1. Causes of Earthquakes
Collapse EarthquakesCollapse EarthquakesCollapse EarthquakesCollapse Earthquakes
Collapse earthquakes are small earthquakes occur inregions of underground caverns and mines. The immediatecause of ground shaking is the sudden collapse of the roofg g pof the mine or cavern.
Dr. Osman Shalan Dr. Tharwat Sakr
1.2.1. Causes of Earthquakes
Large ReservoirLarge Reservoir induced Earthquakesinduced EarthquakesLarge ReservoirLarge Reservoir--induced Earthquakesinduced Earthquakes
The idea that earthquakes might be triggered by impoundingq g gg y p gsurface water is not new. The first detailed evidence of such aneffect came with the filling of Lake Mead behind Hoover Dam(height 221 m. After impounding began , reports of local shakingb l tbecame prevalent.
Dr. Osman Shalan Dr. Tharwat Sakr
1.2.1. Causes of Earthquakes
TsunamiTsunamiTsunamiTsunamiUnderwater earthquakes,volcanoes, or landslidescan produce a tsunami orcan produce a tsunami ortidal wave. This wave cantravel very rapidlythousands of miles acrossthe ocean. In deep waterthe tsunami may only raisethe ocean level by a fewcentimeters hardly enoughcentimeters, hardly enoughto notice. But as itapproaches land, theshallower water causes theshallower water causes thewave to build in height toas much as 10-20 metersor more and suddenly
Dr. Osman Shalan Dr. Tharwat Sakr
flood coastal areas
1.2.2. Faults
DefinitionDefinitionAA faultfault is a fracture within someparticular rocky mass within the
h' Th d h d
DefinitionDefinition
earth's crust. The depth andlength of faults vary greatly.Faults may range in length fromfew meters to many kilometersfew meters to many kilometersand are drawn on a geologicalmap as continuous or brokenlines. Earthquakes are caused byq yactiveactive faultsfaults, that is, faults alongwhich the two sides of thefracture move with respect to
h th S th k ieach other. So, an earthquake iscaused by the sudden movementof the two sides of a fault withrespect to anotherrespect to another .
Dr. Osman Shalan Dr. Tharwat Sakr
1.2.2. Faults
Active FaultsActive FaultsActive FaultsActive Faults
Prof.Dr. Osman Shaalan Dr. Tharwat Sakr
1.2.2. Faults
Tectonic PlatesTectonic PlatesTectonic PlatesTectonic Plates
Dr. Osman Shalan Dr. Tharwat Sakr
1.2.2. Faults
Types of FaultsTypes of Faults a)a) NormalNormal faultsfaultsThese occur in response to pulling
i h l i bl k
Types of FaultsTypes of Faults
or tension: the overlying blockmoves down the dip of the faultplane. movieb)b) ThrustThrust (reverse)(reverse) faultsfaultsb)b) ThrustThrust (reverse)(reverse) faultsfaultsThese occur in response tosqueezing or compression: theoverlying block moves up the dipy g p pof the fault plane. moviec)c) StrikeStrike‐‐slipslip (lateral)(lateral) faultsfaultsThese occur in response to eithert f t th bl ktype of stress: the blocks movehorizontally past one another . movie
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.2.2. Faults
Earthquake Generation (Theory of Elastic ReboundEarthquake Generation (Theory of Elastic Rebound)Earthquake Generation (Theory of Elastic ReboundEarthquake Generation (Theory of Elastic Rebound)
Elastic Rebound Model of EarthquakeElastic Rebound Model of Earthquakemovie
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.2.2. Faults
Earthquake FocusEarthquake FocusEarthquake FocusEarthquake FocusThe point on the fault whererupture initiates is referred to
h ff h th tas the focusfocus or hypocenterhypocenterof an earthquake.
The hypocenterhypocenter of anearthquake is described byq yits depth in kilometers, itsmap location in latitude andlongitude, its date and timef d i
The term epicenterepicenter is thepoint on the earth’s surfaceof occurrence, and its
magnitudepoint on the earth s surfacedirectly above thehypocenterhypocenter
Prof. Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sak
1.2.3. Earthquake Effects
How do Earthquakes affect Structures?How do Earthquakes affect Structures?
1‐ By inertial forcesd b
generated by severeground shaking
Overturning collapse of a high-rise building Chi-Chi earthquake, Taiwan, September 20,Chi Chi earthquake, Taiwan, September 20,
1999, Magnitude 7.6
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.2.3. Earthquake Effects
How do Earthquakes affect Structures?How do Earthquakes affect Structures?
2. By earthquake‐i d d fi
induced fires:
Damage caused by the earthquake induced fires Hanshin (Kobe) earthquake, January 17, 1995, Japan,Hanshin (Kobe) earthquake, January 17, 1995, Japan,
Magnitude 6.9
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.2.3. Earthquake Effects
How do Earthquakes affect Structures?How do Earthquakes affect Structures?3. By changing the physical properties of the foundation soils such as
Liquefaction:
Damage due to liquefactionOverturning due to liquefaction Damage due to liquefaction1964 Niigata, Japan, earthquake.
g qKocaeli earthquake, Turkey, 1999, Magnitude 7.4
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.2.3. Earthquake Effects
How do Earthquakes affect Structures?How do Earthquakes affect Structures?4. By direct fault displacement at the site of a structure:
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.2.3. Earthquake Effects
How do Earthquakes affect Structures?How do Earthquakes affect Structures?5. By landslides, or other movement:
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.2.3. Earthquake Effects
How do Earthquakes affect Structures?How do Earthquakes affect Structures?6. By seismic sea waves (tsunamis) or fluid motions in
reservoirs and lakes (seiches):
Prof.Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr
1.2. Nature of Earthquakes
QuestionsQuestions (refer to Project Group Page(refer to Project Group Pageِ ِ Assignment (Assignment (11))))
Prof. Dr. Osman Shaalan Earthquake Engineering Dr. Tharwat Sakr