foundation presentation .pptx
TRANSCRIPT
Simple Cycle Energy CenterCore Engineering Consultant
Arlington, Tx
Dec 12, 2015
Team of Engineers Ali Shafikhani
Haroon Rasheed
Mohammed Muqtadar
Chhokila Lama
Sandeep Shah
Tenzing Lama
1
Project Outline ● Project Introduction
● Scope: Foundation Design
● Conclusion and Recommendations
● References
➢Turbine
➢GSU Transformers and
Breakers
➢ Four Water Tank
2Speaker: Ali Shafikhani
IntroductionPlant Layout
3Speaker: Ali Shafikhani
543 megawatt simple cycle gas fired electric generating facility in
Maverick County, Texas
Water
Tanks
GSU Transformers &
Breakers
Turbines
Foundation Design
A TM2500 Gas Turbine
GSU Transformers and BreakersA Water Storage Tank 4
Speaker: Ali Shafikhani
Turbine Options
Speaker: Ali Shafikhani5
Mat Foundation Design(for 90% of loads)
● Strong sand layer over weak clay layerEliminating the top clay layer.
Speaker: Ali Shafikhani
Foundation dimension: 23*64 (ft) with huge safety factor
6
Mitigation of Turbine Vibration
loading EffectApplication 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
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.
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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Combined Footing● Strong clay layer over weaker sand layer
Speaker: Ali Shafikhani
Foundation dimension: 4.5*10 (ft). F.S>4
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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
Elastic Settlement Drilled shaft:
● This case: Se= 0.48 inch
Speaker: Ali Shafikhani12
Storage TankWater 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
●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 Shah14
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 Shah15
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
GSU TRANSFORMERProperties 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
GSU TRANSFORMERASSUMPTIONS:
● 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
18
Speaker: Haroon Rasheed
FORMULAS
19Speaker: Haroon Rasheed
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”
20
Speaker: Haroon Rasheed
GSU BREAKERProperties 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
GSU BREAKERASSUMPTIONS:
● 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
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”
23Speaker: Haroon Rasheed
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
24Speaker: Haroon Rasheed
Turbine GSU Transformer &
Breaker
Water Storage Tank
Mat Foundation Shallow Foundation Pile Foundation
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