1. Simple Cycle Energy Center
Core Engineering Consultant
Arlington, Tx
Dec 12, 2015
Team of Engineers
Ali Shafikhani
Haroon Rasheed
Mohammed Muqtadar
Chhokila Lama
Sandeep Shah
Tenzing Lama
1

2. Project Outline
● Project Introduction
● Scope: Foundation Design
● Conclusion and Recommendations
● References
➢Turbine
➢GSU Transformers and
Breakers
➢ Four Water Tank
2
Speaker: Ali Shafikhani

3. Introduction
Plant Layout
3Speaker: Ali Shafikhani
543 megawatt simple cycle gas fired electric generating facility in
Maverick County, Texas
Water
Tanks
GSU Transformers &
Breakers
Turbines

4. Foundation Design
A TM2500 Gas Turbine
GSU Transformers and Breakers
A Water Storage Tank4
Speaker: Ali Shafikhani

5. Turbine Options
Speaker: Ali Shafikhani
5

6. Mat Foundation Design
(for 90% of loads)
●Strong sand layer over weak clay layer
Eliminating the top clay layer.
Speaker: Ali Shafikhani
Foundation dimension: 23*64 (ft) with huge safety factor
6

7. Mitigation of Turbine Vibration
loading Effect
Application of light weight high compressive strength geofoam blocks as structural
void fill material (Ɣ=0.7-2.85 pcf).
- To mitigate destructive vibration loading effect.
- In order to design a lightweight mat foundation to prevent subsequent
settlement.
- To make a cost effective design.
- To decrease construction time period.
Speaker: Ali Shafikhani
Resource:
(https://hayfieldhouse.wordpress.com/category/foundation/)
Resource: (http://cenews.com/article/9649/geofoam-a-lightweight-fill-
alternative)
7

8. Lightweight foundation on
expansive soil
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Expansive soils:
- High settlement and swelling potential during seasonal rainfall.
- Load concentration motivates this settlement and swelling effect.
- differential settlement will occur.

9. Mitigation of Swelling effect of top
Clay layer
Speaker: Ali Shafikhani
Deep foundation dimension: 16*3*5 (ft)
(Resource: Chen (1988), O’Nill (1988))
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10. Combined Footing
●Strong clay layer over weaker sand layer
Speaker: Ali Shafikhani
Foundation dimension: 4.5*10 (ft). F.S>4
10

11. Elastic Settlement
Mat Foundation and Combined Footing:
● Sand layers:
● Clay layers:
● Mat Foundation: Se= 0.68 (in)
● Combined Footing: Se= 0.36 (in)
Speaker: Ali Shafikhani
11

12. Elastic Settlement
Drilled shaft:
●This case: Se= 0.48 inch
Speaker: Ali Shafikhani
12

13. Storage Tank
Water 50,000 gal
Height of Steel Tank = 50 ft
Tank Thickness = 1.5 in
Structural load = Tank + Water
=
418 kips
Bore log 2
Speaker: Sandeep Shah 13

14. ●2 X 2 Group Pile
●Length of Piles= 20 ft
●Circular Concrete Pile
●Diameter = 1.5 ft
●Spacing (S) = 2.5 D
Dimensions
Speaker: Sandeep Shah
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15. Pile Capacity
●Tip Resistance (Sand layer) Qp = 319 kips
(Meyerhof’s Method)
●Skin Resistance (Clay+Sand) Qs = 74 kips
(Alpha & Meyerhof)
●Ultimate bearing Capacity of 4 piles without the
group effect Qu = 1572 kips
●Group efficiency = 1.11 (Piles behave individually)
●Ultimate load bearing capacity of the group pile
Qg(u) = 1572 kips
●F.S. = 3, Qall = 524 kips > 418 kips
Speaker: Sandeep Shah 15

16. Settlements
●Elastic Settlement
➢ Individual= 0.180 in
➢Group piles = 0.33 in
● Consolidation Settlement
➢ Group = 1.15 in
Total Settlement = 1.48in <1.5 in
● Pile Cap
➢ Dimension=6ft X 6ft
➢Thickness=3.3 ft.
➢ Weight= 17.8kips
Group Pile
Weight of 4 piles = 21.2 kips
Speaker: Sandeep Shah 16

17. GSU TRANSFORMER
Properties of Transformer
Dimensions
Width : 65” = 5.41’
Length : 84” = 7’
Height : 96.625” = 8.05’
Weight
APPROX. WEIGHT:
CORE & COIL - 3832 lbs.
CASE - 3011 lbs.
LIQUID (343 gal.) -2744 lbs.
TOTAL - 9587 lbs.
17Speaker: Haroon Rasheed

18. GSU TRANSFORMER
ASSUMPTIONS:
● Pressure bulb reaches a depth of 2B (12’)
● The three layers from the depth of 4’ to 16’ are
considered to be one sandy layer with a ᶲavg of
34⁰ and ϒavg of 115 psf
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Speaker: Haroon Rasheed

19. FORMULAS
19Speaker: Haroon Rasheed

20. RESULTS● Qb = 13123.8 lbs
● Qt = 22800 lbs
● Qu = 21602.45 lbs
● Qu < Qt Hence O.K.
● Qall = 345639 lbs
● Elastic Settlement = 0.6”
● Elastic settlement is less than 1.5”
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Speaker: Haroon Rasheed

21. GSU BREAKER
Properties of GSU Breaker
Dimensions
•Length : 92” = 7.6’
•Width : 78” = 6.5’
Weight
•Weight with gas - 11180 lbs.
•Weight less gas - 10910 lbs.
21Speaker: Haroon Rasheed

22. GSU BREAKER
ASSUMPTIONS:
● Pressure bulb reaches a depth of 2B (12’)
● The three layers from the depth of 4’ to 16’ are
considered to be one sandy layer with a ᶲavg of
34⁰ and ϒavg of 115 psf
22Speaker: Haroon Rasheed

23. RESULTS
● Qb = 15311 lbs
● Qt = 22800 lbs
● Qu = 21289 lbs
● Qu< Qt Hence O.K.
● Qall = 745115 lbs
● Elastic Settlement = 0.56”
● Elastic settlement is less than 1.5”
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Speaker: Haroon Rasheed

24. Conclusion & Recommendation
● Shallow Foundation is the best type of foundation to be considered for
the transformer
● The load of the transformer is less therefore foundations such as pile
foundation and mat foundation are not recommended
● Geo form is used as an anticipate to fill the voids between reinforcing
bars and a part of foundation as it increases compressive strength and
absorbs the vibration of GSU
● For the water storage tank, Pile Foundation is Recommended
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Speaker: Haroon Rasheed
Turbine GSU Transformer &
Breaker
Water Storage Tank
Mat Foundation Shallow Foundation Pile Foundation

25. References
●"Highland Tank - Steel Storage Tanks." Highland
Tank - Steel Storage Tanks. N.p., n.d. Web. 06 Dec.
2015.
●Das, Braja M. Principles of Foundation
Engineering, SI, Stamford, CT: Cengage Learning,
2011, Print.
25Speaker: Haroon Rasheed