*Seismic Hazard to dams *Dams Types *Dams Hazard

1. DIRECTORATE OF SEISMIC STUDIES
TARBELA DAM PROJECT
WELCOME
TO
DIRECTORATE OF
SEISMIC STUDIES

2. A
BRIEF ABOUT
TARBELA DAM PROJECT
&
SEISMIC NETWORKS
AT
THIS PROJECT

4. LARGE DAMS
• According to ICOLD definition of large dams it
• is the one which has at least
• 15 meters of height or storing at least 3
million
• meter cube of water

5. Sr.No COUNTRY NO. OF
LARGE DAMS
1 CHINA >18000
2 USA >7000
3 INDIA >4000
4 JAPAN >3000
5 CANADA >800
6 RUSSIA >200
7 PAKISTAN ~154

6. TYPES OF DAMS
• EMBANKMENT DAMS
• GRAVITY DAMS
• ARCH DAMS
• BUTTRESS DAMS

7. EMBANKMENT DAM

8. EMBANKMENT DAM
• Embankment Dams are massive dams
made of Earth or Rock
• They rely on their weight to resist the
flow of water

9. GRAVITY DAM

10. GRAVITY DAM
• Gravity Dams resist the horizontal thrust of water
entirely by their own weight
• Concrete Gravity Dams are typically used to
block streams through narrow gorges
• Concrete gravity dams tend to use a large
amount concrete which make these expensive
• Generally the base of a concrete gravity dam is
equal to 0.7 times the height of the dam

11. ARCH DAM

12. ARCH DAM
• An Arched Dam is a curved Dam, dependent
upon arch action for its strength
• Arch Dams are thinner and therefore require
less material than any other type of dam
• Arch dams are good for sites that are narrow
and have strong abutments

13. BUTTRESS DAM

14. BUTTRESS DAM
• Buttress Dams are dams in which the face is
held up by a series of supports
• Buttress Dams can take many forms , the face
may be flat or curved
• Buttress Dams are made of concrete and may
be reinforced with steel bars. The buttress
may be hollow or solid

15. MAIN STRUCTURES
OF
TARBELA DAM PROJECT
• Main Embankment Dam
• The Reservoir
• Two Auxiliary Dams
• Two Spillways
• Five Tunnels
• Power House

17. IMPORTANT FUNCTIONS
OF
TARBELA DAM
• SUPPLY OF WATER FOR IRRIGATION
• Nearly four million acres of agriculture land is receiving
• GENERATION OF HYDEL POWER
• 3478 MW of electricity is being generated which is almost 30% of the
total electricity generated by WAPDA and 16 % of the country.
• TARBELA DAM IS THE BACK BONE OF THE COUNTRY
• w.r.t
• THE SUPPLY OF WATER FOR IRRIGATION
• AND
• GENERATON OF ELECTRICITY

18. IMPORTANT INFORMATION ABOUT TARBELA DAM PROJECT
YEAR OF BEGINNING 1968 YEAR OF COMPLETION 1976 COST ~ US$ 2 Billion
TYPE OF DAM LENGTH
(Meters)
HEIGHT (Meters)
MAIN 2743 145
AUXILLARY 1 713 105
AUXILLARY 2 293 67
CAPACITY INITIAL 2015 DECREASE
GROSS 11.62 MAF 7.44 MAF 36 %
USABLE 9.68 MAF 6.5 MAF 33%
NAME OF
SPILLWAYS
DISCHAR
GE
(Cusecs)
GATES SIZE
(Meters)
AUXILLARY 8,50,000 9 15.2 *
18.6
SERVICE 6,50,000 7 -do-
TUNNEL NO LENGTH
(Miles)
DISCHARGE
(Cusecs)
1-3 ½ Mile Turbines Installed
4 ½ Mile 92,000
5 ½ Mile 82,000
UNITS TUNNEL CAPACITY TOTAL YEAR
1-4 1 175 700 1977
5-10 2 175 1050 1982-
85
11-14 3 432 1728 1994
G.TOTAL 3478

19. SEISMIC NETWORKS
AT
TARBELA DAM
PROJECT

21. MAXIMUM EARTHQUAKE THAT CAN
BE GENERATED BY LOCAL FAULTS
• Fault Magnitude
• Darband 6.5
• Panjal 7.5
• Detachment 8.0

22. SEISMIC MONITORING
OF
DAMS AND RESERVOIRS
MAY SERVE SEVERAL PURPOSES
STUDIES REGARDING INDUCED SEISMICITY
STUDIES REGARDING GROUND RESPONSE TO
STRONG SHAKING BEFORE A DAM IS BUILT
STRUCTURAL STUDIES REGARDING SEISMIC
BEHAVIOUR OF THE DAM ITSELF

23. SEISMIC INSTRUMENTATION
AT
TARBELA DAM
• MICROSEISMIC NETWORK
• ACCELEROGRAPH NETWORK

24. WAPDA REAL TIME
SEISMIC MONITORING
SYSTEM AND
DATA PROCESSING
USING
ANTELOPE SOFTWARE

25. COMPONENT OF
WAPDA
REAL-TIME SEISMIC SYSTEM
• Site
• Sensors
• Data loggers
• Communications
• ANTELOPE Software

26. STATION SITE
IN SEISMOLOGY, WHICH IS A TYPICAL NON-
EXPERIMENTAL SCIENCE, EVERY SEISMIC EVENT WHICH
IS NOT RECORDED REPRESENTS LOSS OF DATA

28. • Seismometers
• Weak motion
• Velocity
• Very sensitive
• Seismicity monitoring
•
• Accelerometers
• Strong motion
• Acceleration
• Less sensitive
• Engineering purposes

29. SENSORS AT WAPDA STATIONS
• SHORT PERIOD SEISMOMETER
• TO RECORD GROUND MOTION OF VERY SMALL,
MODERATE, AND LARGE; LOCAL, REGIONAL
EARTHQUAKESFREE FIELD
•ACCELEROMETER
• TO RECORD LOCAL STRONG GROUND MOTION
AND USEFUL FOR BOTH ENGINEERING AND
SEISMOLOGICAL APPLICATIONS

30. LOCATION OF SEISMIC STATIONS

31. LOCATION OF ACCELEROGRAPH STATIONS

32. DIRECTORATE OF SEISMIC STUDIES
TARBELA DAM PROJECT

33. WAPDA VSAT COMMUNICATION SYSTEM

34. REAL-TIME SEISMIC SYSTEM
PROVIDES
FAST AND RELIABLE INFORMATION TO
GOVERNMENT AGENCIES IN RESPONSE TO
SEISMIC EVENT
HIGH QUALITY SEISMIC DATA RECORDING
FOR HAZARD MITIGATION STUDIES AND
SCIENTIFIC RESEARCH
HIGH AVAILABILITY
EASE OF MAINTENANCE AND UPGRADE
LOW TOTAL COST OF THE OWNERSHIP (TCO)

35. ANTELOPE SOFTWARE SYSTEMS
ARTS (ANTELOPE Real Time System)
Real Time Acquisition
Real Time Data Processing
Command & Control
OFF Line Processing
Relational Database
Communications & Power System
ANTELOPE Software

36. REAL-TIME MONITORING
OF
DATA & INFORMATION

37. OBJECTIVES
Calculate seismic risk factor for different
project structures to be constructed.
Calculate the maximum credible
earthquake posing great hazard to dam.
Investigate the seismicity induced by
filling of Tarbela reservoir.
Gather data for exchange with different
international organizations.
Make an attempt for the prediction of
earthquake

38. RESERVOIR INDUCED SEISMICITY
Reorganization in Seismicity is generally
confined up to shallow depths i.e. 20 km.
and limited to a radial distance of about
50 km.
Increased seismic activity associated with
rapid filling/depleting is a direct effect of
loading/unloading through either shear
stress or increased pore pressure. These
induced events are mostly of low
magnitude. However, after quiescence in
Seismicity, felt events may occur with
magnitudes up to 5.5.

39. EXAMPLES OF RESERVOIR INDUCED
SEISMICITY AT SOME DAMS

40. DIRECTORATE OF SEISMIC STUDIES
TARBELA DAM PROJECT
EARTHQUAKE DRILL
BLUE IV
TO V
YELLOW
VI TO VII
RED > VII

41. EARTHQUAKE DRILLS
TARBELA,MANGLA & DIAMER BASHA
Earthquake felt around the Dams may be potentially damaging depending
on their intensity and duration of shaking. a tremor with intensities of vi
or higher on modified Mercalli (M.M) Intensity scale will cause visible
damage. therefore, emergency drill must be called for.
OBJECTIVES:
To take immediate actions to assess the damages.
To take necessary actions to lessen or prevent the consequences of
damages around the Dams and down stream areas.
To evaluate the remedial actions for restoring of functional adequacy of
damaged project features as soon as possible.